in my tank, i have three guppies - two female and one male, along with twelve other fish (it's a ten gallon) and when i got the females, both were pregnant - they had the dark spot behind their fin. now, both dark spots aren't as dark and when the one poops, it's a pink color. they've been in the tank over 24 hours, almost 30 hours and i just noticed that their dark spots have lightened up. is this an abortion? neither one was near ready to give birth.