Acan Help.....
 

Have this piece about 3 months and everything was going fine until yesterday. I noticed a white web like substance(best way i can describe it) covering the coral yesterday morning. I siphoned off the white substance and gave the coral an iodine dip i fragged off any part i could see had totally receeded.

Again this morning it appears to have this web like substance on it. My tank is a red sea reefer nano 29g volume, using BRS lighting schedule for AI Prime HD (similar to Echotec AB), my parameters are

Ammonia- 0
Nitrite - 0
Nitrate - 2ppm
PO4 - 0.1ppm (triton icp test 2 weeks ago)
Alk - 8 dkh
Cal - 460 (i have been reducing slowly from 500 over the past weeks)
Mg - 1370
SG - 1.025
PH - 8.2

Im using Triton other methods at 3ml per day each bottle except 2 (Calcium) at the minute. I use Tropic Marin Pro Reef Salt.

I lost a Frogspawn to when looked like RTN last week.

Just wonder has anyone seen anything similar before and if so have they had any luck in saving the coral. Any help or advice much appreciated. I have attached a few pics of both the Acan and the frogspawn i lost last week.( sorry for the crap quaitly as they are taken from my phone).https://uploads.tapatalk-cdn.com/201...586f7bb9bc.jpghttps://uploads.tapatalk-cdn.com/201...377005a5fe.jpghttps://uploads.tapatalk-cdn.com/201...2960d82447.jpghttps://uploads.tapatalk-cdn.com/201...4f0ab21f25.jpghttps://uploads.tapatalk-cdn.com/201...ce53c062a3.jpg

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Look's to me like they are reacting to to much light back off a bit see what happens... I would run a bit of carbon just in case they are reacting to some chemicals released by the GSP you have in the tank... Good luck.

When did you change the lighting schedule? I only recently saw the brs prime settings, so this could definitely cause issues if changed too quickly.