MH Heat & wattage ?

Like Lunatic said That would be plenty. I'd not worry about any lighting problem's But I would use the UVI aka. URI brand of bulbs.. Best bulbs going , what size is this tank ? And to add as for the chiller I have never had the need for one in my home tanks ever. I have used one just to see what is any difference a rock solid temperature level would have if any .. But I have never had to run one at home.

 

Tangster, the tank will be a 90 gallon. Did having the chiller and keeping the stable temperature make a difference in your opinion? I dont wanna have to redo my plumbing if i find out i need a chiller, rather just get it all done with.

 

Not really I don't think But all you have to do and I'd do it anyways as I always put a manifold on my systems then I can tap off and on with anything with just a flip of the valve . How fans will do for you as I said depends on location and how cool you keep the house ? I have several taps now with Valves just waiting for a need

A little temperature fluctuation is normal and alright like a reef its cooler some of the season and warmer the other time of the yr. several cloudy days and a large storm will make them cooler then a few hot sunny days in a row will warm them up also. So for me a degree or two matters not mine runs about 80 in the summer and 79 in the summer.
I ran a 90 here and in Va with 250 M/Hs and never a issue and I gave one amcarrigs buddies a dual set of 175 M/H for his 55 and they have a full hood also as we did and theirs heated up once but no fans and A/C at all.
I wired a dedicated outlet and control the room A/C through a 20 amp chiller control. If tank hits 80 the A/M comes on tank hits 78 A/C goes off.

 

yes, i use a chiller regardless, check out lumen bright relflectors: less ambient heat exchange