Filtration for ADF

[Mentat]

It depends on total biomass and if tank is planted or not. You got a big well planted tank with couple ADF and can probably get away with water changes only to keep nitrates below 25ppm. However, for a normal smaller tank with few frogs, a small HOB (the small Aquaclears) or a large in tank foam filter work good .

[Vivariums In The Mist]

Definitely a good idea to go with filtration for your tank. HOB filters are easier to maintain in general.

[PolkaDot]

Here's a picture of my setup so far