Head loss for sump in basement.

Fishf00d · Jun 8, 2021

I've read a few posts here covering this topic and have run calculation at this site: http://www.freecalc.com/fricfram.htm. I'm lost at what size pipe to use. My total rise from the sump looks to be about 9ft, but I have two returns on the tank so I have to split the line at some point. Initial drawing had that at about 4ft below the returns in the tank. There is also a 10 ft horizontal run putting me at 23ft of pipe.

I'd also have two 90's and four 45's, the Y and minimum 1 union and 1 ball valve. I could see putting at least 2 other unions if not 3 in there.

Using the Iwaki MD-100rtl, which has 1in inlet and outlet, and 2136 gph with the 1 inch plumbing I'm getting a value of 25.4 head loss before the 9 feet of vertical. That puts me at 35ft without the additional unions added in. That's putting me in the neighborhood of 350 gph for the return.

When I use the same pump but change the plumbing size to 1 1/2 inch it drops the head loss to 3.7 for a total of about 13 which gives me 1050gph.

Does increasing the pipe size really give that much more flow? That seems like an extreme difference.

Tank size is about 160 gal so at 5x turnover I'd be looking at 800 gal.

I didn't think the rise and run were that long compared to some other basement sumps I've seen posted. I was hoping I wouldn't even have to go with the MD-100rtl.

maroun.c · Jun 8, 2021

Yes increasing pipe size does decrease loss as u get less surface friction on the pipe in addition to wider pipe size, if I remember correctly a 1" pipe has less liss than 2 1/2 inch ones .
If possible go with 2x45 instead of the 90.

DCR · Jun 8, 2021

Yes, pipe size does make that much difference. One inch pipe is too small for 1000 gph, especially for long runs like yours. You almost always need to increase the pipe size from the pump outlet. Pump outlets are generally restricted to minimize recirculation and improve efficiency. I would go with 1-1/2" on the main run. You can put a 1" union ball valve right on the discharge and then expand up to 1-1/2". The two splits can be 1". Ideally the suction line should also be 1-1/2" and reduce down right at the pump, but if it is really short and straight you can get by with 1". Avoid elbows in the suction if possible.

I would think an Iwaki 70 which can deliver 800 gph at about 21 feet would work with 1-1/2" piping. You might be a little short of 800 gph but it would save a lot of power.

Cwentz758 · Jun 8, 2021

I'm running a Vectra L2 from my basement to my first floor. its about 25 feet before it goes up about 4 feet before it hits a T then up 4 feet into the tank. I used a lot of 90s due to space

I used 1' tubing all the way to just before the tank due to the fact my tank was drilled for 3/4. I'm running the pump at 49%. I could have it lower if I slowed my flow into the sump but I like the amount of water I'm pushing.

If you could go with a DC return pump that would help as they seem less affected than an AC pump with head loss.

Fishf00d · Jun 9, 2021

DCR said:
Yes, pipe size does make that much difference. One inch pipe is too small for 1000 gph, especially for long runs like yours. You almost always need to increase the pipe size from the pump outlet. Pump outlets are generally restricted to minimize recirculation and improve efficiency. I would go with 1-1/2" on the main run. You can put a 1" union ball valve right on the discharge and then expand up to 1-1/2". The two splits can be 1". Ideally the suction line should also be 1-1/2" and reduce down right at the pump, but if it is really short and straight you can get by with 1". Avoid elbows in the suction if possible.

I would think an Iwaki 70 which can deliver 800 gph at about 21 feet would work with 1-1/2" piping. You might be a little short of 800 gph but it would save a lot of power.

Yea the power is what I was hoping to avoid. I can hook the pump up right outside the sump so there will be little to no run there. The two 90's are a must I think. I don't believe I'll have enough space behind the tank for 45's. I can use 45's everywhere below the first floor. Would flexible pvc be an improvement? I could eliminate all 4 of the 45's if I used flexible pvc. I'm not sure if that would make much of a difference.

Fishf00d · Jun 9, 2021

Cwentz758 said:
I'm running a Vectra L2 from my basement to my first floor. its about 25 feet before it goes up about 4 feet before it hits a T then up 4 feet into the tank. I used a lot of 90s due to space

I used 1' tubing all the way to just before the tank due to the fact my tank was drilled for 3/4. I'm running the pump at 49%. I could have it lower if I slowed my flow into the sump but I like the amount of water I'm pushing.

If you could go with a DC return pump that would help as they seem less affected than an AC pump with head loss.

Ideally I'd love a DC pump but other than the Abyzz and Royal Exclusive I didn't think any would handle that much pressure.

Cwentz758 · Jun 9, 2021

i think you may be over estimating it but heres a DC that pushes 31ft

Cwentz758 · Jun 9, 2021

heck for the price you could run 2

DCR · Jun 9, 2021

Fishf00d said:
Yea the power is what I was hoping to avoid. I can hook the pump up right outside the sump so there will be little to no run there. The two 90's are a must I think. I don't believe I'll have enough space behind the tank for 45's. I can use 45's everywhere below the first floor. Would flexible pvc be an improvement? I could eliminate all 4 of the 45's if I used flexible pvc. I'm not sure if that would make much of a difference.

There is a misconception on this site that using two 45's is less head loss than a single 90. The engineering tools I use in my profession say they are roughly the same. I think BRS even tested it and discovered the same. Creating a long radius elbow with flexible PVC would make an improvement, but if you go with 1-1/2" the frictional losses are going to be relatively small as your calculator shows. You can find more lower power options for 800 gph at 13 ft of head. An Iwaki 55 gets very close at about 12 ft at 800 gph.

Fishf00d · Jun 9, 2021

DCR said:
There is a misconception on this site that using two 45's is less head loss than a single 90. The engineering tools I use in my profession say they are roughly the same. I think BRS even tested it and discovered the same. Creating a long radius elbow with flexible PVC would make an improvement, but if you go with 1-1/2" the frictional losses are going to be relatively small as your calculator shows. You can find more lower power options for 800 gph at 13 ft of head. An Iwaki 55 gets very close at about 12 ft at 800 gph.

With the way things are laid out I could probably use flexible pvc and only have the 90's going into the tank eliminating all other elbows.

Uncle99 · Jun 9, 2021

Cwentz758 said:
i think you may be over estimating it but heres a DC that pushes 31ft

Have this pump in the basement sump, 15ft mostly straight up 1” piping. Only running at 60% and also runs my UV.
Your looking at 15,000 to 20,000lph to lift that water easily and have room to run some media if you want.

jda · Jun 9, 2021

Run the same size that the output of the Iwaki is. Do not upsize it.

I suggest that you consider putting your sump up on a stand for maintenance and also less head.

Fishf00d · Jun 9, 2021

jda said:
Run the same size that the output of the Iwaki is. Do not upsize it.

I suggest that you consider putting your sump up on a stand for maintenance and also less head.

The sump is already up and running in the basement. Its a 6 ft 180 or so. Tank has been ordered. Custom from Miracles 43x38x25. I have a complete water change station plus qt setup for both fish and coral in the basement.

jda · Jun 9, 2021

If you ever get a chance, consider like a 2-3 foot stand for that sump on the basement floor. Just easier to get stuff in and out of and you can siphon gunk out of it into a bucket on the floor... and you can keep your stuff under it. I won't have another basement sump on the ground again. The few elbows and the horizontal run will be nothing for a real pressure rated pump, IME.

Well, now that I think about it, lumber is really high right now, but still probably worth it to build a stand.

I ran a ton of PanWorld and Iwaki basement pumps. I liked to use 1" flex line (the vinyl stuff), but 1" hard is OK too. Larger than this slowed down the flow. Big Laguna submersible pumps could do the job too... Fluval SP6 too. Other than Red Dragon or Abyzz, no DC pump can handle this in the same kind of way - don't believe what any of them say... they are mostly a joke.

Fishf00d · Jun 9, 2021

jda said:
If you ever get a chance, consider like a 2-3 foot stand for that sump on the basement floor. Just easier to get stuff in and out of and you can siphon gunk out of it into a bucket on the floor... and you can keep your stuff under it. I won't have another basement sump on the ground again. The few elbows and the horizontal run will be nothing for a real pressure rated pump, IME.

Well, now that I think about it, lumber is really high right now, but still probably worth it to build a stand.

I ran a ton of PanWorld and Iwaki basement pumps. I liked to use 1" flex line (the vinyl stuff), but 1" hard is OK too. Larger than this slowed down the flow. Big Laguna submersible pumps could do the job too... Fluval SP6 too. Other than Red Dragon or Abyzz, no DC pump can handle this in the same kind of way - don't believe what any of them say... they are mostly a joke.

Here is the sump up and running. Traded a frag of RR The Vinh for the tank and had to take the entire thing apart and put it back together. Its sloppy but it's the basement. I drilled it before I put it back together.

BoneDoc · Sep 21, 2021

Cwentz758 said:
I'm running a Vectra L2 from my basement to my first floor. its about 25 feet before it goes up about 4 feet before it hits a T then up 4 feet into the tank. I used a lot of 90s due to space

I used 1' tubing all the way to just before the tank due to the fact my tank was drilled for 3/4. I'm running the pump at 49%. I could have it lower if I slowed my flow into the sump but I like the amount of water I'm pushing.

If you could go with a DC return pump that would help as they seem less affected than an AC pump with head loss.

How much flow were you getting ?