Why arent my mob spawners working????

Me : CocosetteMax
Lobby : Skyblock 1
Bug Description : I have 2 mooshroom spawners which give me food, they spawn on grass, (i have grass where they spawn too) and they arent spawning. The same happend with my blaze farm, they wont spawn. My slimes arent spawning, but my pigman spawner is working fine??? Please PLEASE PLEASE fix this as we have used money on the spawners.

 

Thanks, But the mooshroom farms are in daylight... i didnt know about the slimes, and the blaze farm is DARK.

 

1.8 mooshrooms no longer spawn on grass. You have to replace the grass with mycelium

 

THANK YOU SO MUCH <333333333

 

Question answered.

./c