Having used both T5HO and PC I can say you would be far better off with T5HO (not t5 NO-normal output-which are ok for freshwater but not reef tanks). PC bulbs will work well the first few months, then turn your corals brown, and after a year they are garbage, at which point they go pollute a landfill. T5 last up to 3 years, cost less, grow and glow the coral, and then they go in the landfill and pollute the earth. Theoretically all flourescents are recyclable, does it really happen? Anyways, you can grow acros, clams and anything else with T5, under PC they will languish. There are of course other variables such as calcium and feeding to this but if you think you might want hard corals and clams set up for that, don't waste time and money on PC. Some think the industry will pull PC units soon as T5 catches on, would not be surprised.
I have heard the actinics got better with the newer versions of T5 HO, is that not true? Has anyone done comparitive analysis of the various brands like has been done with halides? I have definitely seen the actinic t5 bulbs work better than PC actinics if you can judge them by flourescing of the corals' pigments, but is that all there is to actinics?
I am presently using a 4 bulb light with 2 6500K bulbs, a URI actinic blue (weakly flourescing) and a URI actinic white, which actually is pink and ugly. So am thinking of using a 1200K bulb and 2 quality actinic blues, leaving one 6500K for growth. I think it was a Skimmerwhisperer post that turned me onto the 6500K experiment and it definitely does work, thank you... but now the corals are too big so I want to see what will change if I were to use a more typical bulb choice. Will color improve? Will growth slow? I have 2 unused 6500K bulbs to make the experiment fair-all bulbs will again be brand new. These corals were under a different array of t5HO colors a year ago and had incredible color. Now that I need to thin them out and that means selling... I need their color back.
and I like experiments. am hoping some of the serious scientists who can do legit experiments will do a comparative analysis of T5HO products that the rest of us can use... that would be great. Meanwhile guess I will check out giessmans.
Thanks,
Kate