over filtration & filter pipe sharing

I try and overfilter all my tanks. the only ill-effects I am aware of would be too much waterflow for fish that don't like current if you have any. The fish usually like the dirty water since it mimick's most natural habitats but they're not going to complain about the clear water either. the bio-filtration isn't going to be anymore than what is needed so you could put a thousand filters on the tank and it's only going to set up enough bacteria for the tank to support. In essence you are feeding them just as you are feeding the fish so any additional would just starve and die from the lack of ammonia or nitrites. Granted I am basing these replies on my own semi-educated theories and have no scientific training but I think I'm probably pretty close. As for the filter design, I can't comment there because I'm really not too sure what you're even asking and I've never kept those filters either. Kyle

I think overfiltration is a myth. The media houses more bacterial colonies for better biofiltration. I don't use carbon in mine though, mostly just mechanical and biological filtration unless I"m treating something specific. So if my water gets tannic, it stays that way until I change it.

To second the previous message though, some fish don't like strong currents or turbulent water, so if you have a lot of inflow areas, you may find a way to dampen some of them so you don't have so many conflicting currents. Turn outflow tubes towards the tank wall if possible, equip HOB with some kind of diffuser screen if necessary, or try to get them to work together. I my 38 gal has two power heads with sponge filters in each rear corner. One jets softly along the back wall, and the other towards the front corner creating a soft circular current instead of a turbulent spot in the middle if they were both jetting toward each other. There is also a power filter in between.

I do disagree with the statement that dirty water suits the fish better as it mimics their natural habitat - not so IMHO. Any tank is higher density higher bioload and more polluted - technically is eutrophic - in comaprrision to native waters.

I agree that it is not posible to overfilter. As stated, biofiltration is limited by ammonia production from fish and microbes, so cannot be overdone. Mechanical filtration is limited by particle size captured by the particular medium used, but is otherwise open-ended.

How "clean" the water is in fact for me depends more on the maintenance of the existing filters and the water changes done of the tank than on the number and nature of the filters. You can 50 filter turnovers per hour and filthy water if don't do the partials and rinse the media.

Current is a separate and distinct issue - current needs to meet the likes/requirements of the fish housed.