Fluval Flex 15, three chambers in the back, first chamber is full of floss and pothos.
Second has the original sponge, removed charcoal and replaced it with ceramic rings, in the sponge chamber and below it. Then the third chamber, air line coming through the back and down to an airstone beside the pump, above the pump I’ve cut out a piece of grey matala as a barrier and filled the chamber up with k1 micro. Water flows through the floss and pothos and the floss catches the mechanical. Then the sponge and ceramic as bio and then moving bed in the third as additional biofiltration. From what I’ve researched, ceramic has more capacity, but the moving bed is higher performance...handling any swings when I over feed or clean out a sponge.
There’s probably 100 guppies in that tank, plus diy co2 and I’ve never had any trace of ammonia. <3
I realize I’m getting side tracked tho.
The Sen is still looking good and no more scuffles. Knock on wood.