Compost bin earthworms with coffee grounds. safe for axolotls ?

[detamaf]

hello!

i have this relatively new earthworm compost bin, which i have been feeding coffee grounds to.
I've only acquired the coffee grounds very recently but i just thought. what if the coffee fed worms are toxic for the axolotl?

i couldn't find anything on the internet about this. so my question is, does anyone know if this would be harmful for my lotls?

Another question: if you have experience with raising worms, which is your recommended way to purge the worm for feeding the axolotl ?

 

[wolfen]

although earthworms can be used to help with the breakdown of coffee grounds etc.. they can be affected by caffeine and in turn possibly affect any animal which preys on them including axolotls.
because there isn't much information regarding caffeine's effect on worms and if/how they break it down it makes them unsafe to be used as a food source.