UV Light and watts?

[wilddiscuss]

I have been told that you shouldn't listen to the manufacturer and you should go on higher watts than what is called for. I have a 75 gallon. What watt bulb should I get? Is the flow rate important? Let me know. Thanks for your time.

Todd

[woodenfish]

To reduce the waterborne bacteria and algae concentration, I'd use 15 Watt in a 75 gal.

Flow rate should be slow but not too slow, about 120-150 GPH for a 15 Watt UV. For the turbo twisted design UV may be a bit higher GPH.

I think UV manufacturers figure that if they state the best GPH their UV won't sell as well, so they inflate it.

[Cosmo]

Smaller UV's will kill bacteria and algea if the flow rate is slow enough, but won't kill virus's. Buy the biggest UV you can afford while keeping the flow rate within tolerance of the fish (i.e. - you don't want a UV that specs a 1200gph flow rate in a Discus tank). 18 to 25 watt would be the lowest I'd go personally. I normally hook mine to pumps at or below the specified minimum flow rate and don't burn up bulbs.

Remember pumps are normally rated at the outlet, and the UV will most likely be mounted above so the actual flow is lower through the UV than the pump spec.

Check drsfostersmith.com. Their website is excellent for reading specs and flow rates of UVs (and pumps at various heights as well ) They give you far more info than any other website. They also have UVs on sale right now :)

Jim

[FishLover888]

The flow rate should be able to turn around your full tank water within one hour at least. Anything slower than that, the nasty thing in your tank will grow at a rate faster than your UV can kill them.

If you have a 75g tank, you need to find an UV unit that can handle at least 75 gph. I would say about 20W at least. Bigger is better as long as it does not increase your water temp too much.

[wilddiscuss]

Thanks for all the help! :)