CC, suck the hot air out.

Vertex sells replacement fans. I just ordered parts for a Vertex system that is probably 15 years old. Compressor rebuild kit, fan, new diffusers, etc. Needed new diffusers because when the pond owner pulled the old one up using the weighted line the plastic fitting broke and the old diffusers are somewhere on the pond bottom.

www.hoosierpondpros.com

[Linked Image from lh6.ggpht.com]
http://www.pondboss.com/subscribe.asp?c=4
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).