Undergravel filter and powerheads?

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Aquarium Advice Newbie
Aug 14, 2008
Hello have question regarding how many powerheads to use with undergravel filter? And the best kinds. New tank set up 10 gallon to 29 gallon. I have a whisper 30 in addtion to UGF. Wanting to figure out will one powerhead be enough to be used or it has to be two? My son has had 10 gallon tank for 3 years with whisper and UGR W/airstones no cycle problems. :confused:
1 per plate. Airstones are fine for both unless you need the flow from a ph. Drop me a pm I'll show you a kewl way to keep them clean
I would advise against them just because of cleaning. They are a pain. If you do use them I would go with one powerhead, or just an air stone. I had two power heads and a HOB filter on my 10gal and it was like a dishwasher inside. Way to much current, the water was so choppy no matter which way I pointed the outflows. Just my two cents.
Well nothing could be messier than my 3 year old Lilac-crowned Amazon that makes a mess everyday. Not to mention my 12 year old son's room. So little work no problem. If I was to use 1 powerhead with the undergravel filter what would i do with the otherside? And would it be better for reverse flow?
I just read on another forum to shut down/remove the UGF as all it does is throw the gunk right back up into the tank . I shut mine down and now , about 2 hours later ,it is starting to clear up - I hope it lasts . I also read here to take the sponges out as they up the nitrates if not cleaned a lot .
I have a 29 G tank and have had crystal clear water unit about a month ago - now I have this orange haze .
Reverse flow under gravel filters are nice in a planted tank, but it's not very useful in an uplanted tank.

Normal flow undergravel filters will trap the junk in the gravel, waiting for you to siphon it back out. If you're blowing the junk through the gravel and back out again, then you're using too much power. You can either use less powerful powerheads/air pumps or cap off one tube and only use one of them.

If this is a new UGF, it will take time for the bacteria to develop in the gravel, you'll need to be patient and not overstock the tank before it's ready to handle a full load.
So what would you guys advise as to sizing power heads for a two plate (two tube) 90 gallon with additional HOB filters as well. What GPH should I try to draw through the UGF's?
recomendataions vary from 4-6x tank volume per hour, so roughly 360-540 gph for a 90 gallon.

Your UGF should come with instructions that recomend the right size powerhead.

This of course could be affected by the type of fish, and how much current they like. If keeping otocinclus catfish, I'd probably throw more powerheads in there not connected to the UGF up to 10x flow.
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