Fish Quantity And Filtration

[Andrew G]

How many fish can be kept in a 20 gal tank with 80 gal filtration installed? (AquaClear 50 plus an AquaClear 30)

 

[Snooks1!]

You could only keep the same amount of fish as in a normally filtered 20 gal. Upping the filtration is good, but other than taking care of messy fish there's no sense in having that much filtration in a 20gal. Just because you put more open windows in a room doesn't mean you can stuff more people into it, eh?

If you are wanting more fish, your best bet is to get a bigger tank. Just because you have massive filtration doesn't mean the fish won't be cramped or less stressed out. In fact, with that much filtration in a small tank you're bound to have massive currents.

 

[SJ2K]

I wouldnt completly agree, increased filtration (if done correctly), can mean more room for bio media meaning you can keep more fish though there are obvious limitations, aslong as there not cramped and you carry out regular maintenance then over stocking is ok and a strong current can be good aswell, personly I have quite a strong current running through part of my tank and the fish love it.

 

[Snooks1!]

True, but it's much easier just to have a normally stocked tank with adequate to slightly over-filtration, than an overstocked tank with more filtration. Yes, it does provide more room for biological filtration, but I think it's best if you just keep the tank normally stocked. People may decide to up the filtration and it works for them, personally though...I wouldn't risk it.

It also has to deal with what sort of fish you're sticking in the tank...If you're having 80gals of filtration for 10 extra tetras...That's way overkill. Though, that much filtration would be fine for puffers and other messy fish. Don't get me wrong...that much in a smaller tank could potentially be great, but probably unnecessary.

 

[jtipton]

It will increase the bio capacity in terms of ammonia and nitrite processing, but there are a couple of other things to consider. First, you also need to increase the oxygen levels in the water. You may need to add a powerhead or some bubblers if the filters don't cause enough surface turbulence. Often, overstocking will push the oxygen limit, before it ever pushes the nitrogen limits. Second, if there is a power outage, your fish will be in BIG trouble. A normally stocked tank can survive a power outage, because they don't carry a heavy bio-load. If you overstock, you need to make sure your filters will keep running. You can get a UPS in case of power outages. This will provide a short term power supply to the tank. Good luck.