Hello all. I am upgrading to MH lighting, and I wish to purchase a cheap ballast for a DIY hood. Any info would be greatly appreciated, as I am anxious to do this right away.
The cheapest is to use the 6.5K bulbs for mercury ballasts. It is possible to get 250Watts for under $100 for ballast (~$25), bulb (~$60), and socket($5).
If you want to use 10K, 14K, or 20K bulbs, it gets harder to find a "cheap" solution. http://www.thelogicalreef.com has 175 watt 10K setups (ellectronic ballast, bulb, reflecter, and socket) for $205. If I remember correctly the magnetic setup was ~$175. You will have to e-mail them about it since they don't have it on their website.
I would like to find a "cheap" HQI ballasts. But, I have not seen much below the $100 mark.
Perhaps others on this board have found better pricing.
The sockets won't work either. HID sockets only accept HID lamps. They don't want you replacing the lamps with anything other than what they were intended for.
It seems that you can modify some fixtures to hold the 150W DE MH bulbs. You still have to get a compatible ballast.
After spending hours trying to get a handle on the details, I understand why most people will go with a retro kit. The information out there is so incomplete that it is hard to know if a given combination will work successfully.
This thread on nano-reef show how one person did this mod. Note that he had to modify the sockets quite a bit to fit the bulb.
While he doesn't list the ballast, I suspect it is a Advance part #72C5481-NP.