I have a 135 gallon tank. Undergravel filter. 10x water flow. 12 1 to 2 inch cichlids. I was running bubbles off of 4 powerheads now I have gone down to 2 powerheads blowing bubbles. I am concerned there might not be enough oxygen for the fish it has been going for about 24 hours everyone seems fine. Are there guidelines for this. can someone help me out

Your aeration should be fine.

What type of cichlids?

I prefer to run actual air stones in all freshwater tanks. They help with the flow and aeration. Bubbles from a powerhead will not do as much.

On another note, why are you running an UGF? What other filtration do you have?

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Biologist-Professional Aquarium Care-Published Author (Aquarium Fish International Magazine)

Stocking has NOTHING to do with tank volume, it is all about water changes.

You are way understocked so O2 should be no problem. Make sure you have plenty of hidding places as Cichlids get aggresive and territorial when they get older. You also have plenty of room for some of the larger catfish like Porthole cats or Armored cats.

I don't think we can say that. For all we know he has a dozen jaguar or wolf cichlids just waiting to outgrow that tank.

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Biologist-Professional Aquarium Care-Published Author (Aquarium Fish International Magazine)

Stocking has NOTHING to do with tank volume, it is all about water changes.

Hello MT...

Your UGF is a little "old school", but will do a good job of running oxygen through the gravel bed. You will need supplemental filtration, and IMO a couple of Aquaclear 70s (hang on the back) placed at opposite ends of the tank will be sufficient.

I've never been a fan of airstones, to me they don't do a very efficient job of getting oxygen into the tank. A good power filter, will do a much better job.

Just a thought.

B

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