are there heat/moisture issues with built-ins?

[jacksonpt]

I'm giving some serious thought to building in my 44g pent tank. However, I'm concerned that there may be heat/moisture issues if I do. I'm looking at doing something very similar to what Ryan did (hope you don't mind, I borrowed your pic).
I run a 250w MH and will soon be adding VHOs. I also get about 1 gallon per day of evaporation. Should I be concerned about the heat from the MH and/or moisture from all the evaporation on a built-in setup like the one pictured below?

 

[grimm reef]

If the room behind the wall is going to be enclosed there will be heat/moisture concerns, but since you're only doing a 44g you should be ok with just making sure you have the air circuilating with a fan

 

[bigmac]

Heat, that's what chillers are for I'm setting up a 120 in wall, the plan for now is to use one 8"+ fan blowing in and one blowing out. Later on I might vent it out through the roof