I've had the same thing happen recently with some of my Rics which were under 250W MH. One colony I had for 4 years and then suddenly they all turned white and disappeared. Around the time it started happening I dont recall doing anything different to my tank. If anything things were improving because I was bringing my nitrate down from ~10ppm to <1ppm with a few improvements to my filtration (larger skimmer and filter socks).
Salinity 1.025 (refractometer)
Temp 27ºC
pH 7.8-8.1
Ca 400
Alk 10
Mg 1300
Nitrate <1
Phosphate .1 (was higher back then and has always been higher until now)
|