81 is not too high. I have been told 78-80 is the best temp but I can't maintain a temp that low. I run 80-83 and I know quite a few people do this as well. I really would not think a Maxijet would cause a temp problem but maybe. I have 8 pumps in my system ...
*180 gal Display, 100 gal basement sump, 33 gal refugium, 3x250 MH, 2x160 VHO actinics, zoos, some softies, LPS & lots of acros and other SPS.
*100 gal prop tank plumbed into main system w/ 2x96 PC lights and 1x150 MH,