Over filtering?

Is there such thing as over filtration? I read somewhere, and cant remember where, that certain bio balls, or bio media can become a "nitrate" factory? What exactly does this refer to?

Is this only because there would be so much biological filtration that it would turn the ammonia, and nitrites to nitrates? But this is what we want, so why would someone make it almost seem like a bad thing? Whether there is 1 gallon of bio media, or 100 gallons, it would convert ammonia and nitrite to nitrates, regardless??

I don't think you can over filter. You could have a filter that's too powerful for the size tank and type of fish being kept. You wouldn't want a huge filter on a small tank discharging a powerful current with delicate species, displacing the substrate, etc.

Any good filter would be a "nitrate factory". As long as you regularly clean it, I don't know why that would be a problem. My bio media comes last in the filter so it doesn't collect a lot of gunk... unless I put off filter maintenance because I hate it so much! If it looks dirty or plugged up, I gently swish it around in dechlorinated water to clean it up.

The sponges seem more like a nitrate factory to me -- squeezing out a well used sponge -- yuck.

I dont' think you can over-filter. You can however over-do the current in a tank. If fish aren't used to strong currents then that may be a problem for them. It's why I'm building a spraybar for my FX5 in my new tank; to keep the current to a manageable level.

As for the nitrate factory thing, as Aura says any filter is a nitrate factory if it's doing its job. What causes nitrates to get out of control is a buildup of gunk somewhere, whether that's in your filter or your substrate or under your rocks. The only way to lower nitrates is to get rid of the gunk, do water changes and/or have a significant amount of plants (which use the nitrates as food). I rely on cleaning filter media and water changes myself.

Really the amount of nitrates in a tank comes down to how much you feed your fish and how many fish you have. The more fish and food, the more nitrates plain and simple.

Thanks for your responses. It was kind of what i felt too, if the filter is doing its job, its a nitrate factory. Plain and simple.

Only reason i ask is, i have a 110 gallon tank and 2 aquaclear 110s on it. I am slowly putting together a sump, to avoid any issues when these Cichlids get larger


Thanks all!!

A lot of the saltwater reefers won't use bioballs because of the nitrates but I don't think we have anything to worry about.