Different experience here. I have been dosing vodka for over a year on my tank. I use GFO with vodka at a daily dose of 12 ml. Tank is 90% SPS with a medium fish load and generous feeding. Under these conditions I have to dose nutrients to keep my PO4 at 0.01 to 0.03 and my NO3 at 0.2 to 0.5.
With regard to alk, I find that running high alk does not harm my SPS directly, but it makes them more suseptable to STN and RTN from other causes. Thus, I have concluded that in my system a high ALK decreases SPS tolerance to injury (ie, my own stupidity). I therefore like to run my alk close to NSW. Subjectively, my growth rates are no different under high alk conditions.
It is interesting that observations vary with regard to effect of alk in systems that employ carbon dosing. It would be great if we could figure out why.
With regard to alk, I find that running high alk does not harm my SPS directly, but it makes them more suseptable to STN and RTN from other causes. Thus, I have concluded that in my system a high ALK decreases SPS tolerance to injury (ie, my own stupidity). I therefore like to run my alk close to NSW. Subjectively, my growth rates are no different under high alk conditions.
It is interesting that observations vary with regard to effect of alk in systems that employ carbon dosing. It would be great if we could figure out why.