The use of a UV light in the reef (MAY) I'M not saying it will stop it if you have it it now.. UV will benefit with treating and or preventing the spreading of certain coral pathogens. All pathogens must of course be waterborne to be killed they pass through the UV. This means that any biotic disease that will pass through will die off.. Only put this up because some say a UV will not do anything for the a reef tank

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what ever works for you is the way to go!!!!!!!!!

Most UV are woefully undersized. An appropriately sized UV has the potential of being slightly useful. An undersized one is just a waste of money IMO.

The problem with UV is it is not selective in what it inactivates so eventually destroys the good along with the bad. UV doesn't really kill anything by itself, it penetrates the cellular structure of organisms and destroys cells so they cannot replicate or reproduce. By doing this the organisms eventually dwindle and die off due to not being reproduced.

My take is the amount of good things it destroys in a reef systems are necessary as food for lower life organisms which in turn are eaten by higher organisms and so on which is the food chain. Eliminate a part of the food chaim and everything suffers.

Don't get me wrong, I swear by UV for a fish only system or non reef application as they do wonders, but not for my reef systems.

+1. IMO though, if you properly quarantine everything before it goes into your main system, a UV stereilizer isn't really necessary. But, everyone has their own philosophy on UV

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When in doubt, do a water change.

I've got a 12x 36watt turbo twist on my 150 gallon, I understand it does kill some good things, however I think I would rather have the UV then to get an outbreak of something like Ich and be screwed.

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Yep, thats what I say.

As a reefer I can't treat with medications so U.V is the only way..
I once had marine white-spot in My system from a new fish..I never done a thing to treat it.. It was taken care or by the U.V And the fish are fine now.
All things considered I think the pros out way the con's

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Remember people the solution to pollution is dilution... weekly water changes!

I have to disagree on that one, pods and small critters are a necesary part of the food chain in a reef and UV inactivates and wipes out their food supply.

+1 AZ. I don't find that there is a need for UVs if proper quarantining is done. Just my opinion

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When in doubt, do a water change.

When i kept fish only systems I ran UV religously and swear by them in systems with heavy fish loads. I kept many tangs and others for 13+ years and truly believe UV had a lot to do with their success. In a reef application though you need the entire food chain from bottom to top for the best system and UV inactivates a very necessary part of that chain which has an effect all the way up.

You may have a valid point there that something along the food chain is being wiped out.. however my refugium is booming with copepods and amphipods so there finding food all the same IMO.

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Remember people the solution to pollution is dilution... weekly water changes!