hi everyone I need some help please!!!!!1 I have a 15 gallon tank with purple gravel and lots of silk plants. I have 4 fancy guppys (i think 1 is going to have babies) 2 opal groumies, a pearl groumie and 2 discos the discos are laying on the gravel and there gills are moving really fast. i think they might die. also i think theres something wrong with my guppys tales. they seem to be disappearing kind of can anyone help me?!?!!!