How to Build a Carlson Surge Bucket, Part 1

[garbled]

Seawitch submitted a new Article:

How to Build a Carlson Surge Bucket, Part 1

In the late 1980s, Dr. Bruce Carlson, who was the Director of the Waikiki Aquarium, built a surge device based on information he had received from David Powell at the Monterey Aquarium. This surge equipment became known as the Carlson Surge Device or CSD.

The Carlson Surge Device is a time-tested method of creating a surge of water in an aquarium. In the days before DC controlled pumps and complex reef computers, many aquarists had one of these devices mounted to a wall over the tank.

The beauty of the surge device is that a pump degrades over time due to wear or pipe fouling, and slowly drops in flow. The surge device, however, will never degrade in strength, only the period between the surges will lengthen, as the pump feeding it wears down.

The original article by Dr. Bruce Carlson, describes in general terms how to make one of these devices, and why you might want one. The normal environment for coral reefs includes plenty of surging water and chaotic flow. Think of the ocean water moving toward the beach and then receding back. The surge helps bring food to corals and also to remove their waste.

Flow in one direction--laminar flow--is not the best for corals, and it is also not what they are used to.

That original article does not, however, get right down to the nitty-gritty of building one and leaves that as an exercise for the reader. In this article, I will drill down into those finer details of how to build a small-scale one for the home aquarium.

Why do you want one?

So, if you can put a big DC, computer-controlled powerhead on your tank these days, why would you ever want one of these? They can be noisy, generate bubbles, and don't offer the control of a modern powerhead.

Well, I don't know why you want one, but I know why I built one. For years my tank had a 10-gallon Borneman surge device running on it. Every 5 minutes or so, the sound of a toilet flush went off, and a big wave of bubbles and water came out. I hooked an auto-feeder to the surge bucket itself, so the food came down through the surge and into the tank. This worked very well, as it distributed the food evenly throughout the aquarium, and none of it ended up on the surface to be pulled away by the overflow and drains. Additionally, it would often take 2-4 flushes before all the food came out, which gave all the fish plenty of time to eat, and less ended up in some crevice to rot.

Marine fish are pretty smart too, and they quickly learned that the big blast of water sometimes had food in it. This resulted in interesting behavior. When the bubbles started leaking out of the pipe end just before the surge, they would all swim out into the open tank water. Many of them would line up on that side of the tank, excitedly swimming for the food. The blast came out, and they would swim right into the full force of the water, dancing around in the bubbles, hunting for food. Most of the time, there wasn't any, but they seemed to enjoy the blast nonetheless. This meant my fish were out and about in the front of the tank almost all the time. If you wanted to show them off, you just had to wait 5-10 minutes for the next blast, and they were all front and center.

So why not a Borneman surge device?

I ran one of these for about 5-8 years. For a long time, it worked really well, however, it had issues. One issue is that the rubber used to form the seal on the flapper slowly degrades in salt water. This meant that every six months or so, I would have to go hunt down a new flapper, and spend a day or two re-tuning the device. Also, sometimes the float would get stuck, or the chain would fall into the drain, or any number of other annoyances caused me to have to go into the room and fiddle with it.

The Borneman surge is also kind of splashy. When it fills or empties, it likes to splash water up and out of the device and onto the surrounding walls. The sound is not similar to that of a toilet; it is the exact sound of a toilet. So, you get to hear that every day forever. And finally, it creates a lot of bubbles. Far more than the Carlson. I believe the lack of moving parts in the Carlson means less maintenance, less fiddling, and more happy-fish dances.

The big picture:

Before I get into the fine details of putting together this thing, for the benefit of the DIY-challenged among the readers, let me give you the big picture in simple language:

We're going to take a bucket, and there will be three (3) pipes coming out the bottom of the bucket. There will also be some plumbing inside the bucket. Water needs to come up into the bottom of the bucket from somewhere with the help of a pump. My water comes from my sump--which sits below my display tank--and I'm using a pump that's already in place moving water up from my sump into the display tank.

The bucket will fill. (And the bucket will sit above and next to the display tank.) As the water fills the bucket, some other plumbing inside the bucket will create a siphon. When the water reaches a certain point inside the bucket, the siphon will make a lot of water will rush out of the bucket through the second pipe exiting the bottom of the bucket into the display tank. This is the surge. The water rushes out with the help of gravity.

After the surge, after the water level falls rapidly in the bucket, the siphon breaks, and the bucket will start filling again. The process repeats itself. Forever.

The third pipe exiting the bottom of the bucket is an emergency drain.

So, that's all it is in a nutshell. Let's get started.

What parts will I need?

You will need the following bits and bobs. I personally made mine from random leftover fittings I've collected over the years, so you can probably tweak the list a little, or just go right off my list to duplicate my design. My collection of selected spare bits. My surge device looks the way it does because I'm using random spare parts.

Spare parts lying around.

Photo courtesy of Tim Rightnour. ©2018, All Rights Reserved.​

1. 1.5" PVC pipe. About 6 feet or so.
2. 1" PVC pipe, about 2 feet.
3. A 1.5" Threaded/Threaded bulkhead
4. A 1" Threaded/Threaded bulkhead
5. A 1/2" Threaded/Threaded bulkhead
6. A 1.5" Tee, slip/slip with 3/4" threaded Tee outlet.
7. 2 90' 1.5" ABS Drain elbows (the short kind)
8. A 3/4" male to 1/4" NPT* female reducer plug
9. A 1/4" male NPT to John-Guest fitting adapter
10. 4 45' 1.5" elbows
11. 2 1.5" male thread to slip adapters
12. 1 1" male thread to slip adapter
13. 1 1/2" male thread 90'
14. 1 1/2" male thread to 1/2" barb fitting
15. 1 1" male thread to 1" barb fitting
16. Some 1/2" tubing
17. Some 1" tubing
18. An old salt bucket, with lid. I prefer a dark color here, as a white one might promote algae growth.
19. A foot of R/O line
20. A dremel, or hole saws to fit the bulkheads
21. A nice, sharp wood chisel
22. PVC cement and thread tape
23. A bunch of zip ties
24. Some spare 2x4's and a bathtub
25. A saw for cutting PVC. (I prefer a Japanese** saw for this.)
26. A bucket. I used an old salt bucket, about 7 gallons.

*NPT is a US standard for threading on parts. It stands for National Pipe Tapered threads.
**If you're not a woodworker, Japanese saws are known for making straight, fine cuts with smooth edges.

OK, so now you have all the parts, let's get to it!

First step, assemble the siphon.

Never be afraid to apply tons of zip ties. Big ones, little ones, white or black.

This is what we will be making:

Plumbing that will go inside the bucket.

Photo courtesy of Tim Rightnour. ©2018, All Rights Reserved.​

You need to cut two sections of 1.5" PVC, to connect the two elbows to the tee. They will generally end up about 1.5-2 inches in length. The reason we use the short ABS elbows, is we don't have much room in our bucket, so we need to keep the assembly pretty tight. I inserted the pipe into both ends of the tee, and then test-fitted the elbows on, until I figured out where to cut. Don't be afraid to make multiple cuts and sneak up on it. You want the elbows right up against the tee.

Don't glue anything yet. Save the glue for later, we have work to do still.

Now cut two lengths of the 1.5" pipe, so that with the pipe on the bottom of the bucket, the top of the tee is about 2 inches from the top of the bucket. Again, it's not super critical to get this right, as we will be adjusting it a lot during the tuning phase. On the end of one of the pipes, cut a long, roughly 35 degree angle off the pipe, to give it the edge you see in the picture above.

At this point, I took some sandpaper and slightly rounded the edges of the cut, inside and out, so they weren't sharp. This smooths the flow of water into the pipe when the siphon breaks and greatly cuts down on the noise.

Take the 3/4" adapter, and the 1/4" John Guest fitting, apply 2 wraps of tape to the threads, and screw them together into the top of the tee.

Now ziptie the R/O tubing to the side of the pipe with the slanted cut. Position the tubing so it is about 1" above the opening into the pipe, when viewed from the side. Connect it to the John-Guest fitting at the top of the tee, and add zipties until it is secure and isn't stressing the fitting out. You can see in mine, I used one fitting to kind of hold it against the tee, so the tubing exits vertically out of the John Guest fitting and isn't pulling to the side. You could also use a 90 degree fitting here, if you happen to find one at the hardware store.

Now why did we do it like this?

The slant-cut end of the pipe is the part that draws water in to create the siphon. If we left it flat, when the water drains down to below the opening, it will gurgle like mad and make quite a ruckus. With the slant cut, and having smoothed the edges with sandpaper, now it makes a quick gurgle, and isn't anywhere near as loud.

The R/O tubing provides a different function. When the siphon breaks, your pump is pushing water back into the system (the bucket), hopefully quickly. When it does so, it quickly stops the gurgle, and resets the device. However, there isn't much air in the pipe at this point, so what will happen is the water will form a slight siphon and actually move up the pipe and over the U-bend while the bucket is only half full. This means the device fires off once, and then just trickles water out as fast as you push it in with the pump. The R/O tubing keeps drawing in air, and breaks the siphon fully after each blast, so the pipe is ready for the next one.

Also, don't use airline tubing or soft tubing here. It makes the worst sound when it's pulling the air in, far louder than anything else this device will ever make. The R/O tubing is completely silent. It also won't get crushed by the zip ties.

Let's make a hole in a bucket!

Now it's time to cut the bottom of the bucket. You want to take the assembly, and try to fit it into the bucket. It might be tight, but the flat-bottomed pipe should sit squarely on the bottom of the bucket, and the other side shouldn't be touching the sides of the bucket. At this point you might need to go back to the previous step, and adjust things slightly until it all fits in there. In my setup, the end of the slant-cut pipe just touches the bottom of the bucket, and I have about 1.5" of gap if one side is up against the wall of the bucket.

Photo courtesy of Tim Rightnour. ©2018, All Rights Reserved.​

However, it's a pretty tight fit. Flip the bucket upside down, and you will want to take the nut off the bulkhead fitting, and try to place it as close to the edge as you can. In my case, there were little angle braces around the bottom rim, that prevented me from getting right on the edge.

Photo courtesy of Tim Rightnour. ©2018, All Rights Reserved.​

This is where the wood chisel comes in. Slowly and carefully use it to cut away the ridges and other things like writing that will prevent a good seal. A super sharp chisel will make quick work of this, and you can just scrape the lettering right off the bottom with ease.

Photo courtesy of Tim Rightnour. ©2018, All Rights Reserved.
​

The chisel is perfect at scraping and doesn't dig into the plastic like a razor blade will. Once you have it all smoothed out, place the nut where you want the hole, and use a sharpie to draw a circle on the inside of the nut.

Now take a dremel, and with one of those little drywall cutting bits, very slowly cut around the hole. You want to go slightly to the outside of the hole, but don't go crazy. If the tool slips a little, that's ok. What I like to do is cut it a bit small, test the fitting, then slowly widen it out with the tool or maybe a round file.

Photo courtesy of Tim Rightnour. ©2018, All Rights Reserved.​

Don't be afraid to undercut and then slowly sneak up on it. Eventually you will have a nice clean hole, and the fitting will drop in. You should then take a file, or razor blade, and clean the edges of the hole, so you don't have any shards or things sticking out. Sandpaper works well here too.

Drop in the bulkhead, rubber gasket side on the inside of the bucket, and hand tighten the nut. Then thread one of the 1.5" male to slip adapters to the bulkhead on the inside of the bucket, and test fit your siphon assembly. With a little luck, or a little fiddling, it should all fit. Once it does, thread the other 1.5" male to slip on to the bottom of the bulkhead. Remember to use thread tape (about 2 wraps, no more than that) for these, so you don't get leaks.

Now get a hold of some spare 1.5" elbows and pipe sections, and make a small L section out of them. This small L section will be the part that goes into your display tank and will be part of your testing and tuning apparatus.

It helps to have a forgiving spouse...

For this next step, we will be invading the bathroom of your house for a few hours. You could also probably do this outdoors with a 20-40 gal bucket, or various other tubs, or even a pool if you could figure out how to suspend the bucket. I used a tub because it's way easier. No honey, I'm still in the bathroom and you can't come in yet!

Bathroom testing.

Photo courtesy of Tim Rightnour. ©2018, All Rights Reserved.​

Take a pair of 2x4's, and lay them across the top of the tub, so you can place the bucket on top of them, with the bulkhead between the braces. It should be reasonably stable. Now grab any old pump, hopefully somewhat similar in power to what you will ultimately be using to feed this thing, and run some tubing up into the bucket, then throw the pump in the tub. Fill the tub with water, and we are ready to begin!

Ideally, you want the L pipe you made in the last step, to end up so it is at the same depth in the water of the tub, where your eventual display will be. This step is simulating how this will work in your display tank.

So, if in the display tank, you want the top of the elbow to be 3" below the waterline, try to adjust the test tube to have the elbow at the same depth (or adjust the water in the tub, whatever works here.)

Turn on the pump, and see what happens. Generally it always works the first time, and then starts to have issues on the next refill. The water will slowly fill up and will usually go quite a bit above the top of the tee. Keep an eye on it because if you made the tee too tall, it might go above the edge of the bucket. Be ready to shut off the pump. If the bucket fills right to the rim, then take your U tube off and trim about an inch or so off each pipe, and refit.

What you should see is this: When it gets just about to the magical level where it starts to operate, you should see 5-6 large bubbles come out of the end pipe (the business end that will be in the display tank, the L). These large bubbles are the air being forced out of the U in the bucket when the siphon is being formed.

After that, you should see the water level start to drop in the bucket, and then a full siphon will begin. As the siphon finishes, the slant tube will break the siphon with a sudden gurgle. It will then start to slowly refill.

Now we can begin to tune this beast. What should happen, is that it refills, and the water just goes again. It won't, don't worry, we can fix that. First, let's discuss how the tuning works:

• The depth of the L below the waterline in the bathtub impacts the height of the water in the bucket before the siphon starts. The deeper the L is in the water, the higher the water has to be above the U tube before it begins.

• The power of the pump can impact the ability of the slant tube to break siphon. If the pump is too strong, the tube will not fully break siphon, and the next fill will be a fail. You can adjust this by slightly shortening the slant tube, but leaving the other tube in the U alone.

• The height of the R/O tubing above the opening in the slant tube impacts how much air goes into the pipe before it refills. If your bucket fills up part way, and then you see little bubbles come out the end, but it stops filling, you don't have enough air in the U tube. What happened is you still have a partial siphon. Little bubbles bad. Big bubbles good.

• If you need to "reset" it, shut the pump off and let it siphon all the water back down into the tub.

• Listen for air leaks in the U tube. If your fittings, which we have not glued yet, are a bit loose sometimes they will suck in air, and this will ruin the setup. If you are absolutely sure you have the U tube and water top line set right, you can fix this by gluing it up now, though ideally, I prefer to just leave it unglued if possible. I don't ever bother to glue the U tube assembly into the bulkhead. A tiny leak there doesn't matter at all.

• These things are finicky. All the different heights of things impact it. It took me about 4 hours to fully tune mine. I was very frustrated, but eventually it worked, and when it works, it just works perfectly. So just stick it out.
  

So the first thing you want to adjust is the overall height of the U-tube. The height of this tube determines the point at which the bucket transitions from fill to empty mode. I advise very slowly trimming it down until you get a water line you are comfortable with, maybe 2 inches below the top rim. I find it helpful to mark this somehow, so you know where it should be. You don't need the second fill to be operational at this point to adjust the top line; you can just fill it once and let it drain to figure this out.

Now we need to get the refill working. Start by moving the R/O tubing to about 1/4" above the cut of the slant tube. If the second fill doesn't trigger the siphon again (the first almost always works, it's the second that counts), then reset the device fully, move the R/O line up about 1/8", and test again. You can often tell this is the case, by removing the R/O tube from the top, and quickly putting it back in. You should hear a rush of air enter. Keep resetting and moving this line up the pipe, until you find your magical set point. Once you find it, you might want to mark your magical set point on the U-tube.

At this point, you either have it working reliably, or you have thrown it through a window. You can blame the whole thing on me to your spouse, it's OK.

Assuming you are still with me here, what I like to do at this point is leave it running for an hour or so. It should keep working. If it flakes out at some point, you probably have it very close and should only make very tiny adjustments to the R/O tube.

While I had it in the tub, firing away, I also used this opportunity to fully test the patience of my spouse and test various food types in it. Because mine will be primarily used for an auto-feeder, I want to know that food will actually fire out of it and not just rot in the bucket.

I threw a variety of different foods, pellet, flake, and shredded nori in there, and just kind of dropped them in from the top like the feeder would do, all at different water heights. Pellet food for example, would usually fully empty within 1-2 surges. Flake was more like 3, and the shredded nori was probably a bit bad for this, as it tends to get stuck on the sides. It did all empty, but only after 5-6 surges. I think I will avoid that one. I also threw a frozen food cube in, and that emptied in 3 surges.

Now I just have to clean a bunch of fish food out of the bathtub, and we'll continue with our setup next time.

This is the end of Part 1. Tomorrow we will have Part 2. Stay tuned!

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Author Profile: Tim Rightnour

Tim Rightnour has been keeping reef aquariums for about 20 years. During that time he has kept about 10 different tanks and spent countless hours building DIY devices to use in his reefkeeping adventures. He currently has a 125g softy tank, an 80g FOWLR, and an 800 gallon project tank.

Tim's forum name is garbled.

Note from the Editor:

Tim Rightnour deserves a special thank you for having the patience of Job explaining his surge device to me in minute detail to help me understand it and to help make his article the best it could be for everyone. Tim is a pleasure to work with.

 

[ca1ore]

Excellent. I ran variations on the Carlson for many years. I always added an emergency stand pipe to mine ..... just in case.

 

[garbled]

A quick video showing testing of the device in the bathtub:

 

[Seawitch]

@garbled I'll include all 3 videos in Part 2, no worries.

 

[Feet4Fish]

Waiting with mixed patients for the next part. Very intrigued and considering this project for my system! Great write up!!!!

 

[shoggoth43]

The aquaponics guys use a lot of different bell and siphon configurations. One addition I've seen is an upside down small PVC cap that the end of the airline tube sits inside. Supposedly that breaks the siphon very quickly without the need for the angled pipe and with minimal gurgling. Especially if the tubing is a larger size like 1/4 or 3/8" tubing. Not sure if I can post a link but if you go to youtube and do a search for "#464: HOW TO: Better Bell Siphon - DIY Wednesday" that should explain what I mean. The original uses a cup that floats and sinks which just seems unnecessary compared to just anchoring the inverted cap in place. In theory you could double up on the snorkel tubes but I don't know if that would get you much compared with just using a slightly larger tube.

 

[Reef-junky]

That’s kind a cool

 

[garbled]

I looked at doing one of the bell style ones for my project, but the pipe sizes got super large when I started calculating.

Oh.. wait.. you are referring to having the siphon break in a bell. Oh. hey. thats a slick idea. What I thought you meant was the Carlson version 2 or 3 that he later invented, where he uses large tubes inside of one another to form the siphon rather than a U. Like the dump tube is a 1.5", and then you fit a 3" tube over that with a closed end and the siphon forms between the inner and outer pipes.

I'll have to go check out that youtube video and see what it looks like. For me, I didn't care about the noise, because it's in a fish room, but it's not that loud really, and it's pretty quick, not a long drawn out horrible. Part 2 will have a video of mine in full operation with sound.

 

[T Carey]

I built and used a dump bucket type wave maker after seeing one in use at the Smithsonian by Dr. Walter Adey. It was on a 29 gal. long before coral keeping was a thing. I sized it and its feed pump to dump on a 13 second cycle after I asked my father to go to the beach in Ft. Walton beach and time wave frequency. The bucket dumped on one end and the other end had an overflow all the way across the end. It worked very well and there was a noticeable improvement in the tank happiness when it went into operation. I eventually took it down because I got tired of the wave sound 24/7. It did create the surge motion in the water and you could see the caulerpa sway back and forth.

I wish I has kept it now that I am keeping corals I think it would be a good thing for the tank. I made it entirely out of acrylic. I bent most of the plastic with a heater cord made for such things that I picked up at a electronics sidewalk sale.

 

[garbled]

Yeah, I don't have space to make one that can be my primary water motion source, and yeah, they can be noisy. The Carlson is so much quieter than the Borneman I used to run on this tank. It's an in-wall, and when the Borneman reset, you could hear it across the room, right through the wall. This one, from the viewing side, totally silent. Maybe with the bell idea up above it could be made even quieter.

One experiment I did while setting this latest one up, was aiming the output down at a 45' angle towards the rocks, just to see. When it fired, a huge cloud of detritus poofed up out of the rocks and got swept away into the overflow.

I really do feel that it benefits the tank. It's not enough to be the make or break on coral water motion, but the fish were enthralled by it.

 

[Rcpilot]

Always wanted to try a surge device, but the bubbles and splashing have kept the project at bay.

 

[shoggoth43]

If it's high enough to work well, then bubbles and splashing are probably going to happen.

The bell and siphon is the most compact way to create the siphon in terms "floor space" as the whole thing can fit within the footprint of a bulkhead fitting if you needed it to. I've used it for a bean animal full siphon before and it was much more compact than the usual U tube and probably had less volume to purge although nothing beats an open submerged herbie style pipe for compactness.

Most of the time people using the bell and siphon go overboard and use gigantic pipe, but there's not much reason to use a 3+ inch tube and using smaller sizes have advantages in both purging air to start the siphon and breaking the siphon. The gardening guys also include a gravel guard pipe. So by the time they're done, the bell and siphon looks like a 6-8" pipe monstrosity which probably doesn't help people's perception of them. Not to mention they're often looking for the cheapest options so using 2 litre bottles as the bell is common and not exactly "compact".

You could probably use a 1" tube inside the bell and use a 2" pipe as the bell and then if you wanted to upsize the pipe going to the tank to 1.5" or so that 1" pipe won't be much of a restriction at all and may help with the start/stop of the siphon. Bean Animal flows a couple thousand GPH through a 1.5" pipe with a 1" bulkhead and the adapter fittings so this shouldn't be too bad as long as the 1" pipe isn't too long.

The neatest surge device I saw was at Scripps in CA. They had a large dome hidden in a rock and used a vacuum pump to just pull water up into the dome and then vented the dome so the water came dumping out so it just looked like a wave surging over/around the rockwork. Silent other than the vent making a small "tik" noise but probably fairly expensive to run given the cost of a decent vacuum pump and I'm sure that pump is not even remotely quiet but easy enough to put it somewhere else .

 

[Cory]

Nice. Ive got a dual carlson surge on my system. I really like it. If you dont like microbubbles and salt spray and noise its not for you lol.

My system is a reef pond in my basement. I have an overhead sump where the carlson works from. The sump is about 70 gallons and dumps 30 gallons of it in about 10 seconds into the pond. It really made some great flow. I use 3" pipe. One starts first then the other kicks in and goes with it. Ive always wanted to make the dump bucket syle but its too complex for me to make.

 

[ca1ore]

I built and used a dump bucket type wave maker after seeing one in use at the Smithsonian by Dr. Walter Adey. It was on a 29 gal. long before coral keeping was a thing. I sized it and its feed pump to dump on a 13 second cycle after I asked my father to go to the beach in Ft. Walton beach and time wave frequency. The bucket dumped on one end and the other end had an overflow all the way across the end. It worked very well and there was a noticeable improvement in the tank happiness when it went into operation. I eventually took it down because I got tired of the wave sound 24/7. It did create the surge motion in the water and you could see the caulerpa sway back and forth.

Not to mention his and Loveland’s book - still one of my favorites. Got me into algal,turf scrubbers also. Used a dump bucket driven ATS and surge device for a long time.

 

[vanpire]

This does seem cool. My question is would using the Carlson Surge Device result in corals growing to a more natural shape that the standard DC flow pumps most of us use currently?

 

[garbled]

I don't know. Maybe not at the scale I built mine to my tank, however, it was designed by Dr Bruce Carlson of the Waikiki aquarium, who were well known at the time for having some of the most impressive captive coral displays around. I've actually seen the devices in operation there, and they are amazing to behold. (As were the displays themselves)

 

[Pola0502ds]

Maybe it was already mentioned but what size tank is this practical on? Would it be good for a 2’x4’ 80 gallon?

 

[garbled]

On an 80, a 5 gallon bucket would be a tremendous amount of flow, so a 5 gallon might be a bit much. You could however, scale it down. Some of the Red Sea salt buckets (the small ones) might be perfect for that sized tank, and you could use 1" PVC for the piping instead of 1.5".

Mind you, if it was your only flow, and you designed for it in the first place, yes, you could run a 5 gallon bucket on an 80. Your water level will move up and down like 2-3 inches though, so, beware of that. For most people, this is way too scary. But the flow would be reef crest level. (which again, might be too much depending on your inhabitants) I'm not sure how obvious it is in the bathtub video, but if you watch the end of the tub, you can see how powerful the wave action is down there. If this frightens you, then scale down to 2-3 gallons instead of 5, and use smaller diameter piping.

I have seen these made with 1/2" tubing and 1 gallon rubbermaid cereal containers, and they still work great.

Also, one last note, if you don't want the super blast, one thing you can do is make a manifold for the output. T the end off, and then run a pipe a few inches in both directions. Drill holes in the pipe, and you will get many smaller jets of water, rather than one big boom. Additionally, by closing it up like this, you will draw the surge out over a longer period of time, rather than all at once.

 

[P-Dub]

One thing to consider is maintaining a constant flow to your sump if you are using an ATO. That, or you would have to lower the switches to compensate. It seems that you would have to have a tremendously large sump to implement it with an ATO without over complicating things. There are always workarounds, though. Just something to consider if deciding to implement.

 

[garbled]

I actually don't have that large of a sump, but yes, you have to adjust the switches slightly. Essentially instead of having a static line that you keep filled to, you have an upper and lower range, and the ato keeps it in that range for you. In the end, you always have the same amount of water in the system, it's just that the line moves.