Larger Heater for Open Top Tank?
I'm in the process of slowly setting up my 112G tank which will have a clear netting top. I'll be using Eheim heaters and based on their recommendations I should be aiming for 250W. This seems to agree with online heater calculators, however, these calculators assume there is a glass top on the tank (at least all the ones I've found). Obviously with an open top tank there will be more evaporation which means there will be more heat loss. But I'm not sure how much more.
Looking for input and suggestions, especially if anyone ever went from a covered tank to an open top tank (did you have to buy a larger heater).