For the past couple weeks I have noticed that my tank was climbing to an extremely high level of alk (>300 ppm / 16.8 dkh) I had a considerable amount of nitrates (>20). Over the past weeks to try to lower my alkalinity, I did a couple water changes ranging from 30 - 50% of my system (which is about 40 gallons). Of course from my research in the forums I saw some that said a 50% water change is necessary for alk that high, unfortunately I saw another post too late saying that you should never do a 50% water change bc the alk will drop too quick and the change could have massive coral die off. Well a couple water changes later I was able to get:
Alk 245
Calc 380
Nitrate 5
Phosphate 0
Unfortunately after those changes I saw some massive coral die off from my chalices, monti, candy cane and some stylos. Somehow my mushrooms, hammer corals, Duncan's, and some candy cane dont even seem to realize the change in params. The params did not last long bc my alk rose after 2 weeks from 245 to over 300 again. As of today:
Alk 300
Calc 400
Nitrate 2.5
Phosphate 0-.25 (erring on the high side bc it's an API test kit)
Magnesium 1050
Additional notes, I ended up switching buckets of instant ocean, was using the orange lid reef version, but went to the purple top basic salt mix bc I was reading there really isn't too much a difference between the two. I also was concerned perhaps maybe it was my RODI system that was failing, which in turn might be adding additional alk to my system, I checked my RODI today and it came back 0.
At this point my hands are up and I have no clue what to do. I see that it seems like some remaining stylos are starting to bleach, I imagine to the extreme levels of alk in my tank but everything else is hunky dory. Why should I do? How is it possible that my tank was likely fine with this level of alk, and what should I do to lower it to the 8-11 dkh range?
Alk 245
Calc 380
Nitrate 5
Phosphate 0
Unfortunately after those changes I saw some massive coral die off from my chalices, monti, candy cane and some stylos. Somehow my mushrooms, hammer corals, Duncan's, and some candy cane dont even seem to realize the change in params. The params did not last long bc my alk rose after 2 weeks from 245 to over 300 again. As of today:
Alk 300
Calc 400
Nitrate 2.5
Phosphate 0-.25 (erring on the high side bc it's an API test kit)
Magnesium 1050
Additional notes, I ended up switching buckets of instant ocean, was using the orange lid reef version, but went to the purple top basic salt mix bc I was reading there really isn't too much a difference between the two. I also was concerned perhaps maybe it was my RODI system that was failing, which in turn might be adding additional alk to my system, I checked my RODI today and it came back 0.
At this point my hands are up and I have no clue what to do. I see that it seems like some remaining stylos are starting to bleach, I imagine to the extreme levels of alk in my tank but everything else is hunky dory. Why should I do? How is it possible that my tank was likely fine with this level of alk, and what should I do to lower it to the 8-11 dkh range?