Can You Overfilter?

[katykaye]

I have a fluval external 205 filter running on my 125L tank (for aquariums up to 200L). This morning I added fluval U4 for aquariums 130-250L) which I want to cycle. The U4 will stay in the 125L when its ready and the 205 will be moved to another tank.


I'm hoping this wont have any detrimental effect on the fish?

 

[onebto]

Simply no you cannot over filter the more the merrier in my opinion

You can I guess get to a point were you have to much from the point of view of its a waste of money as far as running costs, resources and of course the output flow could be a negative as far as some species which prefer a more gentle water movement but this can be tuned by spray bars .

Regards onebto.

 

[puffer duffer]

imo you cant overfilter so it shouldnt harm fish the only reason not to add a powerful filter is if you have fish that dont like strong flow? i have a external filter for tanks up to 300ltr running on my 125ltr and it keeps the water crystal clear,no ammonia no nitrites and 5 nitrates,flow was very fast so i just drilled bigger holes in the spray bar an all's good.

 

[raptorrex]

I have a fluval external 205 filter running on my 125L tank (for aquariums up to 200L). This morning I added fluval U4 for aquariums 130-250L) which I want to cycle. The U4 will stay in the 125L when its ready and the 205 will be moved to another tank.


I'm hoping this wont have any detrimental effect on the fish?

if i am honest, i would suggest that your tank is now adequately filtered with the two.
unless you are using some form of Chemical filtration, like carbon. over filtering is impossible. but, its just possible, you could have too much water flow. even so, considering the water flow in rivers, your going to need a lot of flow to get there.

 

[waterdrop]

This gets asked pretty regularly and its helpful with this question to separate flow rate from media volume.

Media volume is the really important parameter of filtration and if we look to mother nature we find in some cases she might provide several *acres* of marsh for a fish... clearly she has no worry about overfiltration (just my way of saying that, other than getting silly (like a sump bigger than the tank its filtering perhaps) there should be no downside to more and more media volume.

Flow rate should just be a separate topic and there it comes down to how well you control it and allow for some protected spots for fish perhaps that let them get out of the flow for a bit when they want to. It certainly would be possible to stress a fish badly with just too much flow for what that species was prepared for.

~~waterdrop~~