Hi Everyone! I went to my local pet shop recently with the intention of getting a couple of goldfish to keep in a fish tank I found when tidying my loft. After finding out the size that goldfish grow to I was convinced by the shop keeper that some tropical fish would be a better option for me but.... I now feel in over my depth!!! I have a 21litre tank with two mollies, two guppies and two snails as the inhabitants and I have to say I utterly adore them all! I never thought fish could have so much personality! The problem is one of my mollies seems to be not quite right. I think he is a boy and he seems to have to move his fins a lot in order to get around as well as sort of sinking and spending a lot of time at the bottom of the tank. He also has a small orangey red splodge on one if his sides which has developed over the last week. I'm really worried I'm doing something wrong and hurting them! I woukd be so grateful if anyone could give me any advice or guidance. I just want to keep my fish happy and healthy and as I said before I am a complete novice! Thank you!!!