Originally Posted by Marisa23
The Pleco is tiny, like half an inch long. And all the other fish are tiny as well
I'm sure that is why they told you it would be fine. The thing you have to learn before you buy fish you need to research the species you want and see what its "adult" size will be. This is the most common beginner mistake. You see these cute tiny little fish and think you can have a ton of them not taking into consideration their eventual size and bio-load. So that being said if you do as I said in the other post about WC
's and returning the pleco you will be able to keep those fish in the 5.5g for a couple weeks until you can get another tank, preferably a 15g set up.