UV Question, lamp sel. for it and K for tank itself  11/15/11
Good day everybody, Here I am back at your mercy again. I have been having a small brown algae problem. My uv sterilizer was taking care of it for months. Then I noticed it was coming back again. I cleaned out my pump because it was clogged, and put a new bulb in. I have Corallife turbo twist uv 18watt. Now here's the question. I bought a generic Uv bulb off eBay. Are they as good as the regular coral life bulbs?
<UV lights are actually ordinary fluorescent tubes without the fluorescent coating. The tubes are filled with argon and mercury gas with electrodes on each end. A high-voltage electric current runs through the gas between the electrodes. When one of the electrons from that current strikes a mercury molecule, part of its energy is absorbed, exciting the mercury. The mercury then shoots out the energy as a photon of ultraviolet or purple light.
Normal fluorescent tubes have a coating which catches these photons and emits white light, but UV tubes simply omit the coating. So as long as your new UV lamp has no coating, it should be effective.>
I have a 180 reef. Nitrate, ammonia, nitrite are at zero. ph 8.2 Salt Gravity 1.025, Temp bumps fro 79 to 81. The tank is a 180 tall 4ft long 3ft deep. It has two 150 watt 10000k metal halides and two compact 90 watt actinic. Been thinking of switching to 20000k bulbs to see if that would make a difference. What do you think?
<Higher wavelengths do help controlling algae growth but I would not use all 20K lamps if you have photosynthetic life in your system. Be better to go with two 14K MH lamps.>
Thanks,
<You're welcome. James (Salty Dog)>
Jim

Aquael Unimax 250 UV Bulb Replacement 8/25/09
Hello,
<Hi Jenny>
About a year ago, I purchased an Aquael Unimax 250 canister filter. My 9w UV light bulb has recently gone out and I need a replacement. Upon using Google to search for an aquatics store that sells the bulbs that are
listed as compatible with my unit, I only found two and both retail for at least $30 (Drs. Foster and Smith being one of them, and the other being here:
http://www.frogpondaquatics.com/product/UVC-9W?meta=FRG ).
Upon looking on EBay, it looks as though you can roughly get 2 for $10 + shipping. (example:
http://cgi.ebay.com/2pcs-9W-9-WATT-UV-UVC-PL-S9-TUV-G23-Base-Light-Bulb_W0QQ
itemZ290329452696QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item4398fbe098&_
trksid=p3286.c0.m14
)
My question is, are ones like those on EBay compatible? I don't know much about UV lights and was hoping you could help.
<Are one and the same. The PL-S9 base is the same for both lamps along with the wattage.
Good find, beats the heck out of 30 bucks for one lamp. James (Salty Dog)>
-Jenny A.