True stories. The angel will for sure get too big for the 10 g unfortunately. If the pleco is a dwarf version then the 10g could possibly be suitable for it but if its a common pleco, it grows to a length longer than your tank. I picked up a 29g with filter and hood for $80 which is a good deal, and I know petco randomly has $1 per gallon tank sales which are steals. There's not a whole lot you can do to avoid getting a bigger tank with the fish you have. Sorry to be the bearer of bad news. Pics of the pleco would help to identify it