Rio 32hf
 

okay so i really did it I had no idea that there was too much flow but as I found out there is. today i bought the biggest most powerful pump Rio makes:twised: its the 30hf and for my 90 gallon its too much but that is okay because ive toned it down with a 1 inch ball valve after the water outlet. my overflow cannot keep up at full flow, and even with the aid of my old pump pushing water into the sump it still cannot keep up my hang on overflow is noisy as all heck too how can i quiet things down?? is this amount of flow healthy for my tank? my sand is also moving around because of the amount of flow. any thoughts?

bump?

I run a Rio32hf as the sump return on my 115g and I regret it. Far too much flow, my 30" sump is not nearly long enough (even with several different baffle arrangements I've tried) to shed the microbubbles. I use a filter sock to keep the bubbles down some but it's not really a proper solution, it just helps with it a little.

Unless you have a Herbie overflow, sump returns don't need to give you mondo flow. The general recommendation is to aim for 5-7x volume turnover per hour for a sump return, there's no real need to go beyond that. If you do, you get the noise and you get the microbubbles. You can always increase flow turnover in the main tank itself with a closed loop, powerheads, Tunzes, Seios, Korallia's, etc. (Or even surge tanks.)

I'd consider checking into whether you can return the pump and going with a smaller model. I really wish I had done so. You didn't say what your sump volume is but assuming you have 90g main tank and say an additional 20g in the sump, not taking into account water volume loss due to rock and whatnot, 90+20=110g so anywhere from say 500gph to 800gph at 5' head pressure is the pump you should be looking for.

i have no trouble with microbubbles, the noise is bothersome is it okay for my sand to blow around a bit?

You can try twiddling with Durso's/Stockman's to work with the noise. I find you still need to get lucky to get the noise level to go down.

As for the sand. .. that's your call .. it will end up piling in spots and being bare glass in others. You'd have this problem if you had too much flow in the main tank, ie. not just from the sump return.

If you can live with things the way they are, great, but if you're not 100% sure I'd look at returning the pump before it's too late. 5x-7x volume turnover is all you need, so you can get away with using a smaller cheaper pump.