Hiya peaches, sometimes even a knowledgable source can make a typo or an error and not catch it before printing, Chicken Teeth's idea about the sump sounds good as a solution until you get a bigger tank. I know they are a bit hard to find but a 50g tall or a 50g long is a better choice than the 55g standard, they are 36"x 18"x 17" and 48"x 18"x 13" instead of the 55g's 48"x 12 1/2"x 21", the extra 5 1/2" in width is good for larger fish like your oscar.
HOB filters work fine though they have less room for biomedia than do canisters, I use more than one on larger tanks and like the gph to be 3-4 times the tank capacity. I remove the charcoal from the filter pack and replace it with either filter batting or small pieces of lava rock for a little more growth space for the bacteria. Using two or more HOBs also lets me alternate which one I clean so it helps keep the water parameters stable.
HOB filters work fine though they have less room for biomedia than do canisters, I use more than one on larger tanks and like the gph to be 3-4 times the tank capacity. I remove the charcoal from the filter pack and replace it with either filter batting or small pieces of lava rock for a little more growth space for the bacteria. Using two or more HOBs also lets me alternate which one I clean so it helps keep the water parameters stable.
Merry Christmas!
.... Well, it says to spread the food across the surface and magically watch your fish gobble it up. LOL (just kidding) I knew my big Oscar wouldn't eat the tiny pellets so I hide a couple inside a canned cricket... dropped it in his tank, he gobbled it up, blew cricket juice everywhere..
Nobody has to bother with replying back to me. I am basically just babbling on about my problems.....