, there isn't a significant difference in the performance of VHO
. Each has it's pros and cons. I usually use PC
's because I have found them to be cheaper and they don't require a specialized ballast like the VHO
's do. VHO
bulbs are slightly less intense than PC
's, but as I said, I don't think it's a significant difference. VHO
's are more resistant to corrosion due to the fact that the endcaps seal up around the bulb. What size tank is it? What VHO
combination are you considering? What will you want to keep in the tank?