Something like this
AquaClear 110 HOB
For canister filters ? I own Eheim.
Eheims are solid filters and last for years. You can find them used.
Sunsun are a knockoff that seem to work just fine. I hear good things. eBay or Amazon carry them.
I think 1 or 2 filters designed for a 100g tank would handle your potential bioload better than a bunch of little filters AFAIK. I think it will save you a lot of hassle.
Do you have a pond for the Goldfish as they put on size ?
Spotted Pleco ? Is that a Sailfin ? They can hit about a foot and a half.
Will need a massive tank or heated pond later.
If you are enjoying the Goldfish you could switch to 3 Fancies once you move the pond fish out and the Pleco out. The Fancies should be alright in a 50g.
If you don't have one a Python Water Change System can really save you time and save your back
Enjoy your fish
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