hot sleeper

Ok so my husband and I have a memory foam mattress which is prone to getting hot, but I have sheets on it that are supposed to be cool and the mattress has a gel foam layer that's supposed to help with the heat. Aside from all of that, my husband emits SO much heat when he sleeps. I feel like I am sleeping next to a furnace. If I sleep alone I don't have this issue so it's definitely him. What can I do?? 😷 he also mouth breathes which makes it worse lmao. We also have an extra fan in our room.