flow through the sump

kwirky · #1 05-07-2007, 03:50 AM

I'm confused as to how fast water should be moving through a sump. There are so many factors involved. How much water should flow through it for the skimmer to have stuff to pull out? If that needs to be high, then how about people who use low flow through their sumps to cut down on noise/micro-bubbles?

Anyone with their experiences with slow/fast flowing sumps and what they liked/disliked?

cprowler · #2 05-07-2007, 03:59 AM

I think you want 3 to 5 times the display volume per hour. Check out this link.

http://www.melevsreef.com/what_sump.html

Joe Reefer · #3 05-07-2007, 04:25 AM

I have to agree with Bill, all though I have heard figures higher than that.

I tried for 10+ turnover though a 29 gallon sump, I ended up with 5 baffles to finally stop microbubbles.

SeaHorse_Fanatic · #4 05-07-2007, 05:13 AM

I have just over 3 times flow through my sump. My reasoning for low sump flow is so that the skimmer has more time to skim the water, compared to high sump flow.

Anthony

scumchug · #5 05-07-2007, 07:16 AM

I'm running 12X flow with no noise and no micro bubbles

Delphinus · #6 05-07-2007, 04:18 PM

IMO there's no real advantage to having a high flow through the sump. It's not bad if you can do it, but to me I'd rather look at flow within the tank with things like wavemakers, powerheads, waveboxes, Tunzes, closed loops, etc. etc., and just have the sump as a place to run the skimmer, heater and any other filters or equipment (phosphate reactors, carbon, etc.)

Plus, it's just easier to keep the microbubbles and noise in check. For example I have somewhere around 9-10x volume turnover on my 115g cube tank right now and it sounds like a whitewater rafting river in the sump, and if I take out the filter sock, the tank is literally white with microbubbles. A longer sump would work but I'm restricted to what can fit in the stand so I'm stuck with about 28". I can't put more baffles in and still hope to fit my skimmer.

I think I have about 8x volume turnover on my 75g but because I'm using a 48" sump I don't have the microbubble problem on that tank. It's just sheer luck though, had the sump been any shorter there would have been a microbubble problem. It too has a bit of a whitewater river rapids thing going on. Between these two tanks my basement sounds like Takakkaw Falls. I'm never running sumps with over 5x turnover on any tank I set up next.