AGA overflow and return pump

[Cearbhaill]

90 gallon AGA drilled tank- I did not purchase the AGA overflow system but ordered a Durso standpipe instead.
My question regards the return line.

The 1" overflow will give me 600 GPH into the sump, right?
Is this enough for a 90 gallon tank?
Is there any reason I cannot use the 3/4" return hole for a drain line as well?
How much more GPH would that give me and will it work?

I never understood why they put the return line right next to the overflow- seems it would function better if the return line entered the tank further away from the drain?? If I used both the predrilled holes for overflow I could route the return anywhere into the tank that I want it and get (presumably) more thorough circulation??
(I will probably do a totally separate closed loop system later on, but am just working on the initial system now.)

Also I intend to install one SCWD in my return, and don't know which submersible pump I want- Mag 9.5 or Mag 12??
Is there a better choice?

[Guy W]

your correct a 1" hole will drain 600gph. That probably isn't going to yeild optimum circulation alone.

the 3/4" return, if used as a drain, i would guess would give you 25% less than a 1" hole but I'm not 100% sure on that. I wouldn't use it as a drain though. You don't need thousand GPH of water running through your sump. You just need good circulation. If you do a closed loop in addition to the drain line you'll be fine.

As for which pump, a 9.5 will be fine. Infact you'll probably have to choke it back a bit in order for it to not run to fast.

Guy

[slipknottin]

Originally posted by Cearbhaill
The 1" overflow will give me 600 GPH into the sump, right?
More like 1000 gph.


Is this enough for a 90 gallon tank?
IMO you do NOT want to be running 600+ gph through your sump. That causes noise and uses alot of electricity. Run about 300 gph through your sump, and use closed loops or other water movement devices for the rest.


I never understood why they put the return line right next to the overflow- seems it would function better if the return line entered the tank further away from the drain??
Not much of a difference.. You should have circulation that moves all the water in your tank around pretty well anyways.



Also I intend to install one SCWD in my return, and don't know which submersible pump I want- Mag 9.5 or Mag 12??
Is there a better choice?

Dont use a SCWD as a return, use it as a closed loop device. Closed loops are similar to how canister filters work. They work off siphon and are not open to the air. Run three lines up and over the back of your tank, one for the input to a pump (dont run mag pumps externally) then run the pump output to the SCWD, and put the SCWD outlets on opposite sides of the tank. For pumps get a good external pump. (velocity T3 is one good one)

[DEmigh]

This reply is probably too late to have any effect, but here goes...


origianlly posted by Guy W
the 3/4" return, if used as a drain, i would guess would give you 25% less than a 1" hole

The cross sectional area of a 3/4" vs. a 1" hole is 56% I'm just a dumb Geometry teacher, and I don't know all of the physics involved in this question, but my guess would be that the 3/4'' drain would give you just over half the flow of the 1"