Sump help

[Automaticboy6]

I upgraded to an aqueon 90 gallon RR tank with the mega overflow. I have a 20 L gallon sump underneath. The set up is a 1" acrylic tube draining into first compartment with PS, over the baffles and into my return chamber with a Mag 5 through a 3/4" acrylic tube for return. Every minute or so the ratio of water in the main tank lessens allowing a lot of air to pass through the drain into my sump. This creates what I would imagine a seaworld leak sound to be, ha! Do I need a stronger return pump to keep the flow of water more consistent? Or perhaps a PVC fitting for the drain slowing down the rate of water coming into the sump? Is acrylic a bad idea for use in my sump? Thanks!

[kmmthree]

I am guessing a stronger return pump would be the best bet. I use a Mag 12 on my 75g and a Mag 18 on my 125g

[mFrame]

How much distance below your tank is your sub? The mag 5 looks to be rated at 500gph which will turn over your 90g tank just over 4 times an hour. If the pump is significantly lower than the tank you'll get even less than that.

As for noise, regardless of which pump you use, you should look at something like the hofer gurglebuster. Using it and a filter sock cut my tank noise.

[Benny]

I would go for a larger pump, I use a Mag 9 in my 40G breeder... I am working with 4 feet of head height, 2 3/4" 90's about 5-6 inches of 1 inch braided pvc hose to isolate vibration and slow the velocity. Split into a wide fan shaped return pointed in one front corner, and a flow accelerator pointed in the other front corner. All of that cuts down the GPH of the pump, Much below the rated 950+GPH.

You can always use that Mag 5 to run a reactor or two, or a chiller. Always nice to have a backup pump in case your main dies.

[caferacermike]

The ratio of water draining from the tank to the sump is directly related to your pump. It can only be a 1:1 ratio, unless your pump is to large and sucking your sump dry. The tank can only drain what the pump puts back into it. It sounds like you need a Durso standpipe. Something to raise the level up higher in your overflow chamber and then it also allows air to enter with the falling water, breaking up the suction that can create a siphon that seems like a toilet flushing.

[Timfish]

. . . Is acrylic a bad idea for use in my sump . . .

As most of my sumps are acrylic I hope not!

. . . perhaps a PVC fitting for the drain slowing down the rate of water coming into the sump? . . .

I wouldn't ever restrict a drain line. Actually it sounds to me like there already is some kind of restriction or something causing resistance to cause a periodic syphon effect. Are there multiple elbows or a high spot in the drain line that might be trapping air that periodicly purges itself? A lot of people do use Durso standpipes to good effect especially if you choose to use high flow rates through your sump but I don't see the need for high flow rates and like to keep the drain line as straight as possible.