Plumbing Diameter for Return

[nickkohrn]

I’m into the plumbing stages of my first system with a sump. I have a Waterbox 100.3 that came with metric plumbing. I added unions and conversion fittings, which converted my two drains from 32mm to 1” and the return from 25mm to 3/4”. That is what happened below the tank. The pipes in the overflow box are still metric (32mm and 25mm).

Regarding the return, I want to plumb a manifold so that I can run other equipment off of the return, such as my UV sterilizer and an algae reactor. However, I don’t know whether I need to increase the diameter or keep it at 3/4”.

Is there a benefit to increasing the return from 3/4” to 1” and plumbing the manifold off of the 1”, or should I keep everything at 3/4” since that’s closer to the 32mm pipe that it will eventually get pushed back into?

 

[Big G]

I'd go larger. With each connection you add, the available water volume in the pipe will decrease. That is usually not a problem with a good UV sterilizer as the good ones "control" (slow down the flow of water) the exposure to the UV rays. But you may want to add on other devices later. Go Big!

 

[lapin]

Every new tap will have a different water pressure. Be sure to add valves and one before the return to the tank in case you need to add more pressure for a reactor.

 

[nickkohrn]

I'd go larger. With each connection you add, the available water volume in the pipe will decrease. That is usually not a problem with a good UV sterilizer as the good ones "control" (slow down the flow of water) the exposure to the UV rays. But you may want to add on other devices later. Go Big!

That makes sense. I’ll increase the diameter to 1” then. Thanks!

Every new tap will have a different water pressure. Be sure to add valves and one before the return to the tank in case you need to add more pressure for a reactor.

I didn’t think of adding a valve before the return to the tank. I planned on adding them to the taps on the manifold, though. Will ball valves suffice, or should I add gate valves? I’ll be adding a gte valve to the main drain.

 

[Big G]

Ball valves are really for shut off/on; where as gate valves are for "metering" the flow.

 

[nickkohrn]

Ball valves are really for shut off/on; where as gate valves are for "metering" the flow.

It seems that I should get a 1” gate valve for the main drain, and at least three others for the return and manifold. Since I will be taking the 3/4” return diameter to a 1” diameter, should I keep the manifold at 1” as well? If so, then it sounds like I need a total of four 1” gate valves.

 

[Big G]

I know these are pricy, but having to pull apart your system because a "cheap" valve won't open, etc. is a real pain. Consider these, they are the best, and can be repaired unlike a lot of cheap made in China, PVC pcs are these days: Spears brand valves are the best and consider using "thread x thread" so you can take apart your system and make changes unlike the "slip x slip" that are permanently glued together.
https://www.bulkreefsupply.com/spears-gate-valve-thread-x-thread.html

 

[nickkohrn]

I know these are pricy, but having to pull apart your system because a "cheap" valve won't open, etc. is a real pain. Consider these, they are the best, and can be repaired unlike a lot of cheap made in China, PVC pcs are these days: Spears brand valves are the best and consider using "thread x thread" so you can take apart your system and make changes unlike the "slip x slip" that are permanently glued together.
https://www.bulkreefsupply.com/spears-gate-valve-thread-x-thread.html

Thank you for the suggestion! I was looking at the slip models earlier when I was thinking about adding unions on both sides of them. I plan on adding a, likely more than sufficient, good number of unions to the system. Since it’s a 3’ tank, I don’t have a ton of room to work with, and they should make moving my system and maintenance much easier.

 

[Big G]

thread x thread unions are your best friend .
When I setup my 90 last year, I found a local plumbing supply had a good supply of 1" sch 80 pvc parts like unions, etc. But alas, the Spears valves had to be sourced from BRS $$$. But they have worked flawlessly through all of adjustments I've made to my setup. I've used plenty of the HD/Lowes pvc fittings, valves over the years and they just don't hold up and get very, very difficult to turn for adjustments, usually leading to cutting and replacing. No fun.

 

[nickkohrn]

thread x thread unions are your best friend .
When I setup my 90 last year, I found a local plumbing supply had a good supply of 1" sch 80 pvc parts like unions, etc. But alas, the Spears valves had to be sourced from BRS $$$. But they have worked flawlessly through all of adjustments I've made to my setup. I've used plenty of the HD/Lowes pvc fittings, valves over the years and they just don't hold up and get very, very difficult to turn for adjustments, usually leading to cutting and replacing. No fun.

Is this the type of adapter that I will need for 1” pipes and the 1” threaded gate valves that you linked to?