Okay Mich.. Dude, I am a successful adult financial planner, who lives in Westchester NY and pays her own mortgage and I would have to seriously consider picking up a $170 filter... and I don't have to convince anyone to LET me have another tank... that's big money to a young person (young man, young lady? who are we talking to?) to spend on a filter....
The ratings on filters are usually overstated. I usually divide that in HALF. On my 125 gallon I am running 4 filters that should be enough for over 1,000 gallons based on manufacturers "for tanks up to" ratings.
If you have two filters that are rated for 36 gallons each, go with that, it will be fine for the load you have now, but if you're thinking about adding more fish- because honestly- who doesn't! - you'll need more.
If you are buying a second filter- get the biggest one you can- and by biggest I mean the one that will move the most gallons per hour (Noted as GPH on the labels/boxes) that you can afford. HOBs are just fine- you don't need a canister.
Keep your old filter media BTW- and split it between the two new filters, and yes, two is better than one, that way when you do have the inevitable malfunction- hopefully years down the line, half working is much better than none.
