I checked my alk level and it was a little low so i added some buffer. Recommended dose but i think it spiked and caused one of my birdsnest to bleach. Everything else seems to be okay at this time. Please be carefull when adding supplements and bring your levels up slowly as not to harm your corals. I know better but some times i freak out when levels are down and want them back to normal as soon as possible. Maybe after after this loss i will not make that mistake again. Has anyone else done this before?