Would this work for a tank with bottom RETURNS??

[akskirmish]

yup, thats the big negative. i would have to run that like 7ft which will reduce the output of my pump bigtime.

maybe if i only use one bottom return and run double check valves. then leave the other as a drain only..

That could work-
But remember pressure-that will reduce the flow and cause more pressure that will be pushing through that one hole....

My tank was drilled with really small holes-I couldn't do it that way cause of reasons above.....I ended up drilling them out another half inch to allow for better flow....Luckly I have three in the bottom of my tank....But I am still very limited....

As long as your bulkheads would or could support it that way-I dont see a reason why you couldn't or shouldn't setup that way....

 

[JakeH]

That pipe-tower-thingy sure looks impressive! I still believe the simplest solution is always the best...

 

[Toby_H]

you could turn the T by the check valve flat side up so it is above water level and place check valve to left of the T. place the end of the spillover just above water level. This will prevent almost all back siphoning or draining

I agree with Houie and would make this alteration to your original design…



I completely see where Akskirmish is coming from at feeling his set up is fine with the use of check valves… Yet I also completely understand Jcardona’s opinion of having a secondary fail safe…

Just use redundancy, bro. 2 check valves on each return- 1 at tank & 1 just before pump. It would take an act of god to make 4 high quality check valves fail simultaneously. If you still cant sleep, put another one right after the sump or on the intakes. It works for NASA...

Although JakeH is right, each check valve would have to fail to drain the water… they will not need to fail “simultaneously”. You won’t notice the first one fail, which means you are then relying on the second… you won’t notice it fail so you are relying on the third… etc etc… until your tank drains on the floor. There is a very solid argument that this is unlikely, but still possible. Also, we have to consider what may cause a check valve to fail? Whatever the first one experiences it is likely that the second, third, etc will all experience the same thing (such as small particles backwashing into the returns and holding a flap open).




After considering all other details… My suggestion is to plug the darn bottom returns and bring your returns in from the top. This will cause your pump to deal with some head pressure but it will not be any more resistance than the backpressure of the weight of the water in the tank. This will also allow you the option of using sand and will remove a lot of concern. The only downfall I see in that would be having a return line coming into the tank. Which could be concealed as a spray bar…


Regardless of what approach you choose… it made for a good conversation/read

 

[jcardona1]

I agree with Houie and would make this alteration to your original design…



I completely see where Akskirmish is coming from at feeling his set up is fine with the use of check valves… Yet I also completely understand Jcardona’s opinion of having a secondary fail safe…



Although JakeH is right, each check valve would have to fail to drain the water… they will not need to fail “simultaneously”. You won’t notice the first one fail, which means you are then relying on the second… you won’t notice it fail so you are relying on the third… etc etc… until your tank drains on the floor. There is a very solid argument that this is unlikely, but still possible. Also, we have to consider what may cause a check valve to fail? Whatever the first one experiences it is likely that the second, third, etc will all experience the same thing (such as small particles backwashing into the returns and holding a flap open).




After considering all other details… My suggestion is to plug the darn bottom returns and bring your returns in from the top. This will cause your pump to deal with some head pressure but it will not be any more resistance than the backpressure of the weight of the water in the tank. This will also allow you the option of using sand and will remove a lot of concern. The only downfall I see in that would be having a return line coming into the tank. Which could be concealed as a spray bar…


Regardless of what approach you choose… it made for a good conversation/read

thx a lot for your input, appreciate it to be honest, i think im leaning more towards plugging them up and leaving one as a drain for water changes. for returns, i plan on installing two bulkheads (the tank is acrylic) towards the top of the tank

 

[dennisdeng2002]

If you want you could implement a closed system with maybe a ocean clear or something similar just for mechanical purposes, it would increase turnover rate and keep the debris from settling on the bottom.

 

[IITUFFTOBEATII]

If you are going to run all that pipe just plumb over the top or go through the back. Keep it simple bro.

thx a lot for your input, appreciate it to be honest, i think im leaning more towards plugging them up and leaving one as a drain for water changes. for returns, i plan on installing two bulkheads (the tank is acrylic) towards the top of the tank

Sounds like a good idea right there!

 

[OscartheGrouch]

I agree with dennisdeng2002 and save yourself all the worrying and go with a closed loop system using canisters or something.

 

[Miguel4u2]

Just use the return a little below the water that way it will only take a little bit of water down or put slightly above the water and it will take no water, it simpler that having to returns.