I am setting up a cube shaped viv which at one time was a saltwater aquarium and has 24" VHO lights. My ballast can run up to 4 of them, and I was planning on getting some Coralife Trichromatic 6500k full spectrum bulbs. I believe each bulb is 75 watts. The tank is 24x24x16. I already have it setup as a 2 bulb setup, so it would run about 150 watts or I can bump it to 300 watts by adding two more bulbs. Is 300 watts overkill? Should I run different spectrum bulbs? I currently have what is known in the saltwater world as super actinic, which almost pure blue. The lights are all on or all off, so I couldnt run the actinics only without adding another ballast. VHO's are about as intense as PC, maybe more so.
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You will have a major heat issue with those bulbs and that small of a tank.
Might want to reconsider your lighting options.
I believe that VHo's put out less heat than PC's, I may be wrong but I have owned both types in the past and felt the PC's ran much hotter. The tank is 45 gallons and I have a variable speed fan that will circulate air around the bulbs when they are running. The bulbs would be 4" from the top of the aquarium trim. Personally I dont think heat will be the issue... but hey Im a newb to frogs but not aquariums and other related hobbies.
Posts: 1,119
Threads: 118
Joined: Jun 2004
Best of luck and let us know how it goes!
Trying it out is about the only way to know for sure what your temps will be. But I would venture to guess that 150 watts will be plenty of light.
Based on my experiences with 3x96w bulbs on my 46 gallon, I think if all your lights are running on one ballast and can't be switched on and off separately, you're not going to be able to run them al and keep temperatures under control, especially if the tank is only 16" tall. If you can stagger the bulbs on separate timers you can use more of them to simulate dawn, noon, and dusk. I run one bulb from 8am to 3:30pm, one from 10:15am to 5:45pm, and one from 12:30p, to 8pm. This gives me a shift in color temperature and light intensity throughout the day. My temperatures vary from 68ish when the lights come on to 78-79 at 3:30, then slowly drop back down as the lights shut off. Right now, at 3am, temps have just dropped back below 70. To keep temps under control I have 2 high powered (loud!) fans in the canopy, moving about 60 cfm each. I tried running all 3 lights for 5 hours one day and my temps at ground level hit 84 degrees, so even if VHO bulbs do put out less heat than PCs I don't think you could run 300 watts for very long.
On the plus side, within a week of adding the third light my Brassavola nodosa put out 3 new growths, my Cattleya schilleriana put out one, and my Potinara 'Hoku Gem' put out two.
