I'm wanting to purchase sponge filters with air stones for my 75g Betta community as well as my 20g betta tank
I already have HOB so the sponge filter will just be an additional filter for over filtration and surface agitation as well as Oxygenation, will I need 2 Med size for my 75g or will 1 be enough since I already have 2 HOB in that 2 tank? It is HEAVILY planted
Thank you so much for any advice
Tara