power heads

Now that i put them half way down the tank it is not doing it. But the ajustable thing is almost under water.
 
cool did not relize that was the same size. Thank you .
 
Hmm.... I have a aquaclear powerhead for a 30 gallon and my tank is also 30 gallon. It is still cycling and has 1 fish with 30 lbs of live rock. The powerhead is at about 175gph. Is that okay for now? I'm planning on FOWLR with inverts. I'll get some more powerheads later hopefully
 
Also are a couple of 30 gallon power heads better or one big one? like maybe a 50 gallon one?
 
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