Quote:
Originally Posted by Canarygirl  Hi there, introducing myself to the forum in this thread.
I am gradually switching over my 120 from mixed reef to still-mixed-but-mostly-SPS tank. I currently have 2 175 watt MH (Iwasaki 15K), and 2 54 watt actinic T-5's. This averages out to only 3.8 watts per gallon and according to the 5 watt minimum rule it's not enough. However, I have read about the PAR ratings of various MH lights and the ones I've got are top-notch. Doesn't that make a difference? For the record, my tank is 24" tall and I have a tall canopy (15") so my lights are quite a ways above the tank. I will be installing luminarc mini reflectors very soon.
What do you think? Do I need more light to succeed with SPS? |
Because of the bulbs you are using they have a better par value than some of the 250w 20k bulbs. Also, you will be using Luminarcs which are incredibly good at reflecting light. It does sound like you put a lot of thought into this since the coloration will be a theoretically nice crisp white. I bet your tank will do well and your most light demanding SPS will be located at the top. I know the 5 watt min rule isn't the best but it still is relatively low in intensity. I'm not saying in your instance you need to add more light. But factoring in height above the tank and within the tank I think you'll eventually want at least another 150w-400w.
On a side note I would be curious to know what your MH PAR value is for a single bulb at the bottom of your tank.