Too much filtration?

[hefeweisse]

I'm looking for a filter for a recently purchased 30 gallon tank (approx. 30 x 12 x 20). I wanted to purchase a larger filter because I want to someday upgrade to a 55-70 gallon. However I've been recently told by a friend that too large a filter can produce oxygen levels that are "too high," causing fish to die off. She said she saw this fact in a book about fish diseases. I was wondering if there was any truth to this. The only thing I could think of is that it would cause too much current for the fish, but I figured the 20 inches of water would buffer any extreme currents. I was looking at either the emperor 400 or penguin 330 filters.

All advise is much needed and appreciated as I need to set up the tank asap.

Thanks

[Rue]

I'd try the AC 70, but reduce the flow to it's lowest level.

I think you'll have better luck than with the Emperor...

[Northernguy]

You can never have too much filtration,just too much current.
I would also go with an aqua clear HOB filter.They have a better desined filter media (No cartridges) than other filters and are easier to maintain.
We usually double up on filtration around here.If you have a 55gal tank go with an ac110.A 35 is good with an ac 70...

[aspects]

You can never have too much filtration,just too much current.


AMEN!

most filters will give you 3-5x turnover for properly stocked (or lightly stocked) tanks. for "overstocked" tanks, or inhabitants with a higher bio-load, 10x turnover is not uncommon at all. i have had tanks with 20-60x turnover with no problems at all.
as long as the current isn't too much for your fish, there is no such thing as too much. if anything, more filtration is better.

i would also suggest the AquaClear 70 for your 30g and an AquaClear110 for larger tanks. .

[Lab_Rat]

Too high of oxygen can actually cause gas bubble disease but I highly doubt that it is anything you need to worry about. I've got tons of filtration on all of my tanks and some are heavily planted.

[lowlight]

As long as your fish can get out of the current so they can rest you should be fine. I believe what one means when they say to much oxygen in the water is the air bubbles. There can be so many fine air bubbles that it makes the water look cloudy. The air bubbles get trapped in the gills of the fish and I think (not positive) that's what causes gas bubble disease. It also depends on the fish you want to keep that should determine the amount of current you want. Some fish like calm water and some like to get blasted. Do some research feel free to ask questions. Careful planning can lead to hours of enjoyment.