After one week of adding 25ml of 5% vinegar, I see a clarity of water improvement that I had not observed in sometime. Part of the observation was a new attention to the tank which has been suffering from "too many tanks" syndrome. It has been neglected.
Because of my awareness of carbon dosing principals, I have put this tank unto the road of recovery. I had let it get taken over in areas with macro algae which were interfering with the DSB operation. Also complicating the issue was removing macro from the refugium and replacing with nitrate test study winners: bioballs and rock rubble. Two weeks ago, I put Ulva in the macro section of the refugium and turned the lights on with the same cycle as the display tank. An evaporating fan comes on at the same time to control temperature. Initially, it happened this way because of only one timer. As I have further embraced natural cycles, I decided that the normal pH fluctuation, observed on natural reefs have a purpose, that is unknown to me. I trust nature and decided to forgo the opposite photoperiod that is imbedded in the hobby. To start with, I see two advantages. First, the effect of vinegar on pH is offset with photosynthesis in top and bottom. The second advantage is the increased automatic buffering/dosing at night time from arroggonite sand beds.
Removing the UV sterilizer was the third change in 2 weeks.
I now observe some soft coral polyps extended at nighttime, that did not extend previously, both GSP and Green Nepthea are feeding. I suspect bacteria have more to do about it than pH.
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