T5 to VHO or MH Equivalency

[Spracklcat]

Hello all,

I have a 29g running with 3 x 75W VHO's (half and half actinic/10,000K) that I am rewiring for T5 bulbs. Does anyone know the PAR equivalency of T5's to other bulbs, or Watts or lumens equivalency? For example, if I want the same amount of light as 225W of VHO, how many 24W T5's do I need? I know they are more efficient, cast more PAR, but how much? I do want to add more light to the tank, but I want to do it gradually so as not to shock the corals.

Thanks!

Christine

 

[fritz]

PAR is a measure of wavelength more than intensity. Lumens is a measure of "Brightness" PAR is a measure of light within the wavelength useable for photosynthesis. For example a 20,000k 400 Watt Mh bulb will have a much lower par than a 6,500k 400watt MH bulb.

T5s if cooled by a fan blowing right on them and utilizing an individual parabolic reflector and using a 6,500k bulb, have a VERY high par. T5s of that nature are up around MHs and have a much farther "punch" than VHO bulbs which do not penetrate water very far.

 

[cali_reef]

Christine, I don't think there are much testing on the VHO vs. T5 PAR, you can borrow my Apogee Instruments Quantum meter if you want to measure your setup to better acclimate your corals to the new light.

Personally, I would stick four bulbs and icecap reflectors on that tank(I think thats all you can fit in there), it will be brighter and still save 100W of electricity.

 

[Spracklcat]

Sweet. Thanks guys. That's what I'll do then--