how much flow through sump?

[6stang9]

im looking for a return pump for a 92g rr tank with a 20g sump is a mag 9.5 too much or not enough?

 

[MCary]

If you have a heater and skimmer in your tank you need to have enough flow to feed your skimmer and keep your main tank warm and thats about it. Flow in the main tank can be accomplished with power heads.

Mike

 

[6stang9]

i do have heater and skimmer in sump so do you think a 9.5 is good? thank you

 

[crumbletop]

That was too much for me. I have read that 3-5 times tank volume through the sump is what to shoot for. That would be ~240 - 450 gph for your tank. I started with ~900 gph through my 20 gal sump for my 90 and had trouble with microbubbles. I cut back to ~300 gph which is plenty for my heater to keep the temp stable.

RE powerheads for flow -- I agree with this. You get more bang for your buck with powerheads, and they don't have to overcome gravity to give you flow, so you'll end up needing less watts which = less heat. You could also go closed loop for flow, but I don't have any experience with that...

Jack

 

[crumbletop]

One other thing to add -- you could do more flow through the sump if you have large drain pipes (mine was 1 inch) and/or if you have multiple overflows. The AGA handles ~600 gph or so, so pushing more than this causes turbulance and bubbles -- at least that was the problem I was having. I'm much happier with reduced flow...

Jack

 

[MCary]

If the pump on your skimmer is say a Mag 7, with the flow restriction of a skimmer, your probably pushing 500 gph through the skimmer. In that case you would want at least 500 gph going through the sump, otherwise your just recycling alot of already skimmed water.

If your main tanks temp is too low, but the sump temp is hot then your also not running enough.

I would guess a mag 9.5 is fine. You will lose some flow from head loss, but you should be pumping 700-800 gph.

Mike