I should of responded when I saw the thread about the sizes of the keepers.. someone posted the wrong gallons for each size. The mediums are actually 1.75gals. I can clarify if you give me the dimensions, but if it's 11.75" L X 7.75" W X 8" H, then hate to burst your bubble and say that, it's the 1.75g one.
It looks to me that it's that size, comparing your fish to the size of it.
I have a medium and its a 3 gallon... but it is a different brand (trust me, its 3 gallons.... that or I have 2 gallons floatin in mid-air)
Thanks! I also have a lone CoryCat in there who is convinced she is a Goldfish and a Pleco. And my Goldie actually is that big. He's grown a lot. Which is good. Means he isn't stunted. He's about 3" now opposed to the 1.5 I got him at.