Ok I have 2 Cryptosheros Septumfasciatus (Convicts) that are about 2.5 inches each that I have in a 16 gallon bowfront. Well lately they have started to completely rearrange the tank they have been moving mouthful's of sand all day long everyday for about 3 days. I am unable to tell which fish is female and which is male but one of them has this tube looking thing in front of its anal fin. And I was just curious what it is. That one also keeps going into one of the clay flower pots that I have in the tank and swimming around in circles in side the pot. They also kept biting the **** out of me when I was rearrange there tank so yeah any help with this would be awesome. Thanks in advance.