Undergravel Filters Yes Or No?

[Adolf88]

A high performance canister linked to a 8-10 cm deep medium grain gravel bed would work well together, forming a reverse-flow undergravel filter. Eheim, for example, sell kits of converting their canisters into reverse-flow undergravels.

You have to keep the substrate more or less the same depth throughout, so if the fish do a lot of digging, then the undergravel filter won't work so well. A gravel tidy could be used to prevent this sort of problem; i.e., go to the garden centre, get some sturdy green pond mesh cut to size, and put that on top of most of the gravel, topping it with about 2-3 cm of gravel leftover to hold it in place. A few carefully positioned rocks or roots would add extra security.

Cheers, Neale

Now I've got the size of tank I'll be getting a 6" by 2" by 2", could you link me to in your opinion a good external filter that will work well with an UGF as well? I just love looking at the tank with tubes in the corners with power heads on, I think it looks ace

 

[Ludwig Venter]

I am of the old school and have a load of these in operation..... I will recommend undergravel filters to anyone who cares to ask..... I have had tanks with undergravel filtration that stood for 8 years with just water changes (and sand vacuuming) and no indication of fouling or ammonia buildup..... Value for money is an undergravel..... (there are obviously better filters on the market - but costwise..... nothing which matches)