there is a lot of DIY here in MFK, just use the search feature. but the cheapest i have used was 2x cascade 1500. $300 for both. But you can check cragslist for filters.
lol having the same issue. im just going with 2 ac110s for now because im only putting a baby channel catfish in there. thinking about the fx5 or a smaller canister to make sure im reaching deep in the tank.
I am always amazed to see people willing to spend money on new tanks and new fish but not on best filtration possible After all, a filter is the aquarium's heart, lungs, and liver. Does it make sense to go cheap on this life-support system? Not that cheapest is bad, I am just curious about the emphasis. Especially without mentioning the stocking level, which is crucial information...
A couple Hydro V sponge filters and an airpump will be cheapest ...