RTN... Will ozone or UV help?

[aussiefishy]

As stated... I have these RTN a couple time/year, while my parameter seems stable... Will any of these gadgets help??

Also, i found a couple black crabs (with hairy legs) around my liverock that are growing quite rapidly... and i suspect they are nipping my SPS's. will crab induce RTN? :?:

I should note, the piece of coral in question was 6 inch+ by 4 inch+ colony. it has gone completely white with brown skins peeling off overnight.

 

[chineseknife]

It is possible that a crab nippeed, or maybe scraped the coral. If conditions were right it could have had some tissue loss. A full scale RTN overnight, probably not.
I would check Ca, Alk, Ph. Was there a loss of flow? Any recent additions to the tank.
This happens a couple time a year? Yikes.
Is it seasonal. Could be a temp issue if the temp in the tank has risen due to the warmer weather.

 

[aussiefishy]

The temperature seems ok, in fact this happened after i installed a new fan, so the temperature should be cooler somewhat. i have also found out that my dKh has been shot way up... from 10.4-15.4 within a week, possibly due to a overtuned calcium reactor!!! i think that is what caused it.

I have read some books that mentioned RTN and it is bateria/viro related, i am just wondering if UV/Ozone will reduce this likelihood..