Hello everybody,
I am in the process of setting up a 75 gallon planted FW tank (48x18x21). Initially, I will try to run the tank without CO2 fertilization. I am going to build the stand and the canopy myself. For the canopy, I plan to order the AHS PC lights, but I am not sure which ones:
First of all, on the AHS site, they claim the efficiency is about 65% higher than other reflectors with the same bulb. If I try to target 2 - 2.5 wpg, that would suggest that I only need 1.2-1.5 wpg, i.e. 90-115W. In addition, 2 wpg with NO FL used to be considered medium to high, and the PC bulbs deliver a much higher output with the same wattage. That would mean that 2x55W would be OK (decent but slowly growing plants), 4x36W would more than enough (faster growing plants), and for 2x96W I would definitely need CO2. Am I correct or completely wrong?
Assuming that I would go with the 2x55W, one of the issues I read about the AHS PC lights seems to be that they are very narrow and focused. Moving them away from the water surface would probably increase the spread. Where is the optimum between loss of efficiency (due to the distance) from the water and spreading the light? Has anybody experimented with that? It sounds from some of the posts that bending the reflectors would increase the spread. How does impact the efficiency?
Thanks for your help,
Frank
I am in the process of setting up a 75 gallon planted FW tank (48x18x21). Initially, I will try to run the tank without CO2 fertilization. I am going to build the stand and the canopy myself. For the canopy, I plan to order the AHS PC lights, but I am not sure which ones:
First of all, on the AHS site, they claim the efficiency is about 65% higher than other reflectors with the same bulb. If I try to target 2 - 2.5 wpg, that would suggest that I only need 1.2-1.5 wpg, i.e. 90-115W. In addition, 2 wpg with NO FL used to be considered medium to high, and the PC bulbs deliver a much higher output with the same wattage. That would mean that 2x55W would be OK (decent but slowly growing plants), 4x36W would more than enough (faster growing plants), and for 2x96W I would definitely need CO2. Am I correct or completely wrong?
Assuming that I would go with the 2x55W, one of the issues I read about the AHS PC lights seems to be that they are very narrow and focused. Moving them away from the water surface would probably increase the spread. Where is the optimum between loss of efficiency (due to the distance) from the water and spreading the light? Has anybody experimented with that? It sounds from some of the posts that bending the reflectors would increase the spread. How does impact the efficiency?
Thanks for your help,
Frank