I was going to put my Pleco in a 300G pond i have outside. Other residence Are Sword Tails and three gold fish. My only concern is the weather here in the central coast of Calif.. We are entering winter and the night time temps are starting to run in the 40's, a few nights in the 30's maybe 5 day's in a season and daytime 60's to 75. Will the temp. be a big issue?