Personally, I wouldn't keep goldfish and tropicals together for all the reasons already mentioned. Also because I keep real plants in my tropical tanks and goldfish eat them all.


As far as algae eater... plecos are useless, so here's what you need:

1. Otocinclus catfish (aka oto-cats in the aquarium world) are voracious eaters of algae. They only get about 2 inches long, so get a small group of them.

2. Ancistrus- there are a variety of species which all remain under 5 inches long. We keep bristlenose ancistrus currently. They do eat algae throughout their entire lives. They can be expensive, though, but are well worth the investment.