Plumbing for 2 returns, 1inch or 3/4

[Lex_510]

Plumbing a 75gallon display tank and I have a 1500gph pump and 1 inch drains. My question would be, is it best to do 1inch or 3/4 drain with 3/4 bulkhead lock line. Trying to have the best flow less pressure loss

 

[lapin]

I would try to match your pumps output size.

 

[ReefPig]

I would try to match your pumps output size.

I beg to differ, a little.
As a general rule, you want to step up your return pipe by one size as coming out of the pump. As when you account for multiple bends and other restrictions, this doesn’t then have the back pressure effect on the pump.

 

[Rjramos]

Need more info. You said 1” drains. That means you have 2 overflows, each with a 1” bulkhead at the bottom, right? Do you have 3/4” bulkheads at the bottom of the overflow for water return from pump?

 

[Lex_510]

Need more info. You said 1” drains. That means you have 2 overflows, each with a 1” bulkhead at the bottom, right? Do you have 3/4” bulkheads at the bottom of the overflow for water return from pump?

im drilling and putting the eshopps large overflow box with 3 1inch drains in the middle of the tank, and I plan on putting 2 returns on each side

 

[Lex_510]

I beg to differ, a little.
As a general rule, you want to step up your return pipe by one size as coming out of the pump. As when you account for multiple bends and other restrictions, this doesn’t then have the back pressure effect on the pump.

even tho I’m going to T- split for 2 returns? I was thinking 1inch to the T then 3/4 or keep it 1inch all the way to the 3/4 bulkhead or does it not matter ‍

 

[Alexdiaz]

I'd go with 1 inch drains for sure, it will give you some wiggle room just in case down the down a hermit crab decides to make its way down your overflow into the brain. With a larger drain you will possibily prevent a flood.

 

[Lex_510]

I'd go with 1 inch drains for sure, it will give you some wiggle room just in case down the down a hermit crab decides to make its way down your overflow into the brain. With a larger drain you will possibily prevent a flood.

yes for sure 1 inch drains, but what about returns, is 2- 3/4 ok for any back pressure, will have a 3/4 lock lines Coming into tank

 

[Saltyreef]

yes for sure 1 inch drains, but what about returns, is 2- 3/4 ok for any back pressure, will have a 3/4 lock lines Coming into tank

I have a 1" jebao return thats stepped down to a 3/4" loc line Y at the water line.
No issues for the pump. Been running for years.
1" eshopps drain.

 

[Rjramos]

im drilling and putting the eshopps large overflow box with 3 1inch drains in the middle of the tank, and I plan on putting 2 returns on each side

Much better for clarification, thanks. Is this the eshopps overflow? It’s rated at 1000gph, which gives you approximately 13 gph turnover on a 75 gallon tank. You mentioned your pump does 1500gph. If you want to use this pump I would gate the discharge down to about 1000gph. Trying to push 1500gph through this tank is excessive and unnecessary.Use a herbie drain with your overflows 3- 1” drains. Come out of pump discharge with union/ball valve, T off 1”x3/4”x3/4” then to opposite corners of your tank with selected nozzles attached.

 

[Variant]

I recommend going with dual 1" returns instead of 3/4" returns to reduce the velocity at which the water comes out into your display tank. You should rely on your powerheads for water flow / reach instead of using your return pump.

 

[Rjramos]

Look at the chart. You don’t need 2-1” returns for adequate turnover in a 75 gal aquarium. 1- 3/4” line with the minimal friction loss you have, can handle 1400 gph! 2- 1” lines split to the back corners are gonna give you more volume, but not necessarily more velocity. Velocity is determined by reducing the nozzle size, like placing your finger over the end of garden hose, or going from 3/4” pvc to 1/2” loctite and placing a flared or further reduced nozzle at the end.

 

[Lex_510]

Much better for clarification, thanks. Is this the eshopps overflow? It’s rated at 1000gph, which gives you approximately 13 gph turnover on a 75 gallon tank. You mentioned your pump does 1500gph. If you want to use this pump I would gate the discharge down to about 1000gph. Trying to push 1500gph through this tank is excessive and unnecessary.Use a herbie drain with your overflows 3- 1” drains. Come out of pump discharge with union/ball valve, T off 1”x3/4”x3/4” then to opposite corners of your tank with selected nozzles attached.

thanks for the clarification on the 1inch to the T out to 3/4s that may work, and the pump is a DC adjustable pump so should be good with no ball valve

 

[DCR]

Look at the chart. You don’t need 2-1” returns for adequate turnover in a 75 gal aquarium. 1- 3/4” line with the minimal friction loss you have, can handle 1400 gph! 2- 1” lines split to the back corners are gonna give you more volume, but not necessarily more velocity. Velocity is determined by reducing the nozzle size, like placing your finger over the end of garden hose, or going from 3/4” pvc to 1/2” loctite and placing a flared or further reduced nozzle at the end.

That column is for 20 to 100 psig of average pressure which means you should have a pump that with a head of over 200 ft at 1400 gph to push it through a 3/4" line. People need to stop referencing this chart as it is intended for high head, high pressure loss spa systems. 1400 gph coming out of single 3/4" line would literally rocket over the sides of your tank. That is enough flow to fill a 5 gallon bucket in about 12 seconds. Imagine that much flow coming out of a 3/4" line. Sizing piping as a profession, I would not design a single 3/4" line for more than about 400 gph so I think that your conclusion that two of them is adequate for a 75 is still correct. I would still probably run 1" as it is not that much more difficult to deal with, and you will run at lower speed and power consumption if you plan on using a DC pump.

 

[Rjramos]

That column is for 20 to 100 psig of average pressure which means you should have a pump that with a head of over 200 ft at 1400 gph to push it through a 3/4" line. People need to stop referencing this chart as it is intended for high head, high pressure loss spa systems. 1400 gph coming out of single 3/4" line would literally rocket over the sides of your tank. That is enough flow to fill a 5 gallon bucket in about 12 seconds. Imagine that much flow coming out of a 3/4" line. Sizing piping as a profession, I would not design a single 3/4" line for more than about 400 gph so I think that your conclusion that two of them is adequate for a 75 is still correct. I would still probably run 1" as it is not that much more difficult to deal with, and you will run at lower speed and power consumption if you plan on using a DC pump.

My point being that 3/4” pvc can handle lots of volume if the pump has the pressure. Even if he could put 1400gph in the tank with his pump, his drain rate would not keep up through his eshopps overflow.

 

[Llyod276]

Also gravity has less pressure. Literally 1 atm. And 3 drains is excessive. No need. Matter of fact. My 75g has a dyi pvc "overflow" (but mine is a siphon based) 1". And my return (from some pump, dunno what kind) is 3/4 pvc. I'm not running a dc so I have a ball valve controlling the return. Nothing regulates the sump line, just siphon and go. The ball valve is a ****** way to control the return. Very hard to dial in. And either the dt is a bit low or the sump is way high... to safely hold the over flow in the event of a power outage, I try to keep the tank 50% empty that fills the 20g dump to the brim...

 

[JoshH]

I recommend going with dual 1" returns instead of 3/4" returns to reduce the velocity at which the water comes out into your display tank. You should rely on your powerheads for water flow / reach instead of using your return pump.

+1 on this.

 

[Lex_510]

That column is for 20 to 100 psig of average pressure which means you should have a pump that with a head of over 200 ft at 1400 gph to push it through a 3/4" line. People need to stop referencing this chart as it is intended for high head, high pressure loss spa systems. 1400 gph coming out of single 3/4" line would literally rocket over the sides of your tank. That is enough flow to fill a 5 gallon bucket in about 12 seconds. Imagine that much flow coming out of a 3/4" line. Sizing piping as a profession, I would not design a single 3/4" line for more than about 400 gph so I think that your conclusion that two of them is adequate for a 75 is still correct. I would still probably run 1" as it is not that much more difficult to deal with, and you will run at lower speed and power consumption if you plan on using a DC pump.

so if running x2- 1inch returns, would it be ok for the 3/4 bulkhead at the display tank for the flex locklines

 

[Llyod276]

Just asking are you running g a sump? Because how do expect your bacteria to eat anything in such a a huge overturn? Let the water sit a little, no need to have so much flow. But hey man if your trying to recreate Cape Hope, then do it up...

 

[Lex_510]

Just asking are you running g a sump? Because how do expect your bacteria to eat anything in such a a huge overturn? Let the water sit a little, no need to have so much flow. But hey man if your trying to recreate Cape Hope, then do it up...

Just asking are you running g a sump? Because how do expect your bacteria to eat anything in such a a huge overturn? Let the water sit a little, no need to have so much flow. But hey man if your trying to recreate Cape Hope, then do it up...

Yes sump, with a fuge, and skimmer. And your right will need less flow to give the skimmer more to pick up things. I just figured with all the/ T splits, elbows, height/foot loss, and maybe installing a manifold would be a lot of back pressure loss. At least around 600gph of loss