Power heads in 20 Gallon Hex???

Hey everyone,

I'm new to the forum, and new to reef tanks in general. i am starting with a 20 gallon hex that i picked up for free. ive got the filtration system all figured out, but the only thing i am stuck on, is a powerhead. I picked up a Cobalt 1200 which is rated around 300 GPH, and installed it into my tank. i have around 16lb of fully cured live rock, and have been running for about a week now. i decided it was time for fish (mind you, this is to be a fish and reef aquarium... nothing crazy, but a little of both).

Well, i dropped my fish in the other day, and it seemed like they were getting blown around quite a bit by the powerhead. i had it mounted up near the surface, about an inch or two submerged. It was aimed slightly downward, and towards one of the front panels. But, no mater where i aimed it, it moved so much water that it was creating ripples in the sand on the bottom, and seemed to be disturbing the fish. (i have 1 clown, and 1 Bengii Cardinalfish) Needless to say, i took it out.

I need recommendations on a pump size, brand etc. as well as how to properly aim it to ensure that i am not blasting the fish around the tank, but am providing enough water movement still for a small amount of reef. Please help!!!

 

Hi and welcome to 3reef.

Personally I tend to think 300 gph should work well and the fish will adjust.

I have good luck with Koraila. The Nano is 240 gph and that was not enough for me but it might be exactly what you're looking for.

Hydor Koralia Nano Circulation Pump/Powerhead

Congrats on your newer tank!

 

I definitely recommend Koraila, I had one 750gph in my 20G long, and it was plenty xP But two of the nano's would be perfect, keep one pointed in an upward direction to get good surface agitation, and make sure you have one oriented kind of "into" everything. Your overall goal with it is to avoid dead spots.

I do have a question though, If you were to orient them so that they were facing the same direction- on opposite sides of the tank, would you get a whirl pool effect? Would that have any benefit?

 

Welcome to 3reef!!

I'm sure you will get the help you need from the great members here.

I have a 36 gallon tank and have a Koraila at 750gp and for me it didn't move enough water so now I have it about 3" inches from top blowing upward. It creates nice ripples on the water and gives it the ripple effect for the LED system..Ory