[Amberjp]

I'm going to be getting a 20 gal long tank and I'm going to have 3 male betta in it(divided) and was wondering what sponge filter would be best? I'll be getting three filters

Option A: Ista Bio-Sponge Filter - Small // Aquarium Supplies Canada - Pond Supplies Canada - Reptile Supplies Canada // Pets & Ponds

Option B: Deep Blue Professional Hydromaxx 10 Sponge Filter For Aquariums up to 10 Gallons // Aquarium Supplies Canada - Pond Supplies Canada - Reptile Supplies Canada // Pets & Ponds

Option C: Aquatop Classic Aqua Flow Sponge Aquarium Filter Up To 10 Gal CAF-10 | Petland Canada

 

[Hallyx]

The CAF -10 is the smallest. You can install a filter in each bay, running off one airpump.

The Deep Blue and Ista are better quality, but I don't know if either will accept an airstone for better efficiency and less surface disturbance and less noise. These take airstones Sponge Filter - ATI-