Join Date: Mar 2003
Location: Peaches, Peanuts & Cotton
Well let me tell you from experience..........HOBs are not the way to go on the bigger tanks.
Now I only have a 55g, but I do run 2 HOBs on it, since it carries such a large bioload.
In the long run, the costs of cartridges every few weeks to a month, is gonna break you.
If you run 2 AQUACLEAR 500's on a 75g, then you are talking about needing about $66.00 - $68.00 for the filters themselves and then approx $8.00 - $10.00 every time you go to change the carbon inserts.
Pretty quickly, you will surpass the initial costs of a canister filter.
You can go to Big Al's Online and get a Rena XP3 or a Fluval 404 and it should only run you about $95.00 and then you are only talking about needing to replace/ clean media every few months.
If I could do it all again, I would definitely go with a canister!!!!