Red Stringy Worms and RTN

[kevinpo]

NSW (natural seawater) averages 1.026SPG. I keep my stony coral tanks at 1.025. 76F - 82F is OK for most corals. I begin to worry about a few at 83F. I have experienced tissue loss at 84F and above on a few corals.

Ideal parameters for high light (shallow water) SPS corals IME are:

1.025SPG.
Temp. 78F.
Calcium 400-420ppm.
Alkalinity 2.97-3.5 meq/L (8.3-9.9dKH).
Magnesium 1200-1300ppm

Most often it is not a single event that triggers RTN but rather a combination of several factors that deviate far enough from the center of the range to have a cumulative effect.

Regards,
Kevin

 

[roblou]

Brandy: have you tested your Alk level lately? I ask because I had an issue recently where I was doing large water changes (20%) using RC salt. RC has pretty high Alk when mixed (around 11dKH). After I did a few large WC over the course of a few days, I noticed a few (not all) of my SPS were STN from the base up. I measured Alk and found it was at 11. I attribute this to my large WC and also the fact I was continuing to dose my regular schedule (via Litermeter).

Once I found out my Alk was high, I turned off the litermeter for a couple of days so the Alk would drop back down to 8-9. Since then, the STN seems to have stopped.

Dunno if this is the case with your tank or not, but thought I'd pass on my recent experience.

rob

 

[brandyrb]

Both the calcium and alkalinity were low when the RTN started. My husband brought them back up to where they need to be and our salinity is now 1.025. The RTN appears to have stopped on all corals except one, so it wasn't a total loss. Pretty soon we'll be setting up a larger tank with reactors and an auto top off system so we don't have to manually add fresh water, calcium and buffer all the time.

Thanks everyone.