Gymshoes

Thanks for the tips! My concern about a heater is not to "cook" the creatures in the tank. The mini heater will only raise the temp 4-5 degrees, which should be OK since I live in an area with very mild winters. My secondary concern---which came up when I looked at a 25 watt heater in a store this past week---is that it's too long not to touch the substrate. All heaters have warnings not to touch the glass, rocks, substrate, bottom, etc. My tank has a depth of 8"---less with the substrate. The mini may be the way to go...