Soak them in boiling water from the kettle, repeat a couple of times and then leave standing in the last boil for 30 mins..
Get a second opinion to make sure the stones and slate are ok to have ina aquarium ( i dont want your fish to be harmed)
When guppies inbreed, you can get many that are deformed and weak etc...
I try to not let this happen but having so much fry, its hard not to let it happen, in all the time i been breeding guppies, i have been lucky and not had many deformed ones, some that have been have actually grew up and survived well though..
I like to just experiment with diffrent types of guppies, mixing them etc, but its not easy...
First you have to make sure you get virgin ones to breed with a specific male, and this also can not be easy as, you need to get her at a early age, seperate her from any males, and to be fully sure, wait a few months to see if there is no sign of fry, when you know you have a virgin one, you can mate her with a desired guppy..
You cant go by the gravid spot either as virgin females can still develop this without actually been pregnant
