I remodel out basement this year and installed a 5ft X 5ft and 3 1/2 high indoor tutle pond. It has a 45 mil liner and is set up with 2 lights one for heat and the other for UV. it hold 800 gals of fresh water and we have 5 tutles in it. We are trying to find a heater for this tank only thing we find are 300 watt heaters. can anyone advise me where to find a heater big enough and what temputures are ideal for our tutles. Mark

You are lucky to have an indoor pond and many turtles! What species of turtle do you have? What is the temperature in the basement? Aquariums heaters don't go much over 300 W. Unless you have tropical turtles, they may not need too much extra heat. The lighting itself generates enough heat to bask if it's close enough to the water and strong enough. You can add more incandescent heat lamps if they need more heat. A few 300 W heaters where the turtles can't break them might also help raise the temperature just a few degrees if that's all that's needed. Outdoor ponds can be heated by running heated water in cables under the liner. The heat is normally from a indoor pond furnace. I doubt you'd need that much extra heat.

If you want to share photos of your indoor turtle pond on my site, it would be helpful to those with indoor ponds, turtle ponds, and turtles. Good luck!

depending on the species, some turtles can get rather cold. RES for example live here in texas and it can get pretty chilly.. down in the 30s and lower. my 3 RES live outside in the elements, but they normally hibernate.