If you are going to do it, I say over do it.
I am new at this never kept fish before, So i looked at a lot of stuff re filtration on youtube, Moving bed filters, Powerheads with shampoo bottles, Under gravel filters, The powerhead with shampoo bottle while a cool idea looks ugly full stop. same as internal moving bed filters, both take up tank space that could be used for plants or swim room for the fish. those under gravel filters.... Well I just figured they suck, I dont want stuff building up in the gravel even thou I vac it. hang on backs are ok however I would need to cut the glass top on my tank.
Also as I was using a 20 lt tank originally the canister gave me extra water volume. So canister it was, and it was about the same as an internal powerhead unit. Since I watched all those videos on youtube I had a fair idea about media so 1 tray is full of BioHome media and the other with those ceramic noodles.
This is the filter I have. I got it on ebay.
Aqua Aquarium Filter External Canister Fish Tank Water Sponge Pond 800LPH
This is the 1 I was looking at.
Hailea Internal Aquarium Fish Tank Filter Sponge Aqua Power head RP-600 WARRANTY
See why I went with the big canister?
Biohome Mini Ultra Bio Filter Media 1 kg - for Fresh Water or Marine Aquarium
I have this 1 as it came with the filter.
1.8kg Ceramic Noodles Rings Aquaponics Aquarium Canister Filter Media Tank cnr
I also built a power head vacuum, It's a great idea and works well you can give the gravel a good clean without worry about water levels in the tank, after I vac the gravel I change some water about 25% with aged water I put it in a bucket overnight with a powerhead running and some Prime water conditioner, Oh yes I also stick a heater in the bucket so when I add the new water it is the same temp as the water in the tank.
The catfish sound cool, I will have to add extra food for them as there is no wasted food in my tank, He gets a combination of pelets and frozen and fresh bugs , however his daily portion size of food is equal to about 6 or 7 pelets. I feed things to him 1 at a time LOL, Even his brine shrimp.
The pelets I feed him.
Aqua Delight 200g Betta Siamese Fighting Fish Food Pellet