How much over filtering is too much?

[briannesbitt]

We have a 45 gallon bowfront and all has been running since early June with fish in.

We have a two HOB filters, a Fluval C4 and an AC30. Our AC30 we got used from a friend and every time we do a water change (and turn it off/clean it out) it never seems it will start working again. It makes some loud noises (even with water priming) and finally starts up. Anyway, I am thinking of replacing it and was wondering about just getting a second Fluval C4. Would that be too much filtration or more specifically water current for the tank? I am thinking it would be ok and also be easier as I only need to stock one type of filter media as well. (I haven't changed it yet, just rinsing so far: http://www.amazon.com/gp/product/B003SJKVVI/ref=ox_sc_act_title_3?ie=UTF8&smid=ATVPDKIKX0DER but eventually it will need to be changed completely).

Our fish stock consists of a pearl gourami, zebra danios, black skirt tetras, bleeding heart tetras, neon rainbow, couple of corys and a striped raphael.... ie. nothing too delicate.

Thanks for the input!

[robt18]

He only problem if say you could run into is if there's too much water flow for the fish. If there isn't enough fish waste to sustain huge bacterial filters, bacteria simply won't grow. I use two 100+ gallon canisters on my 55gal and everyone is quite happy!

[daworldisblack]

You can overfilter as much as you want (I currently have a Eheim 2028 and a 2213 on my 25 gallon lol) so long as the flow isn't affecting the livestock. If you feel the combined flow won't equate to a mini sinkhole in your tank, I'd say you're going to be swimmingly fine. Not too sure if the C4's have the ability to dial down flow but that could be another option too. Or you could cut flow by placing the filter behing a hardscape. End of the day, overfilter as much as you want, without increasing the overall flow to crazy levels and you're good I'd say.

[lucius]

For your AC30, clean out the inside of the motor unit and impeller a bit, it's probably got algae and muck in it.

Something I noticed with the AquaClear filters is that if you have the water line below the lip of the filter, the water will flow downwards.  If you raise the water line so that it touches or goes over the lip, the water will shoot towards the front of the tank.  On my 20 gallon, I have two AC30's for a total of 300 gph and I have the water shooting towards the front.  My glowlights swim back and forth without any issues.