cmon is there anyg difference in the halides used for hydroponics and sewage treatment (algae scrubbers) i mean the price difference is incredible, are aquarium people screwing us?
The bulb temperature is different. Kind of an analogy would be putting a vita lite on your reef instead of a reef light. But, if you read some of the threads, they say that you can use lower K lighting with the same results. When I was still using MH lighting, I bought a fixture at a hydroponics store for $100 and I used the bulb on my reef without noticing any problems on it. Of course, it was wedged in between 2 others with the right spectrum.