pfoxgrover
Active Member
Abiotic precipitation on an acrylic display tank is nothing I would wish on my worst enemy. If you take a look at the video this amount will take me about an hour of scrapping wityh a plastic short handle scrapper appying all the pressure I can manage. This is the worst side of the tank but there are 3 other sides this big that all have some but not nearly as much.
Also all this scrap[ping is adding fine scratches to the tank. About a month ago if I scrape off all the precipitation it could come back as fast as 24 hours, not that amount takes about 2 weeks to get to the state like in the video. Alyway I am trying to stay the corse but open to feedback on what I might be missing.
Based on Randy's advice that I found on here I have been trying this for a few weeks with some comments in blue
The recipe for reduced precipitation is:
1. Lower pH. Switching to bicarbonate will help considerably. (to keep nighttime PH above 7.8 and daytime not higher than around 8.17, I've been dosing 1 part NaOh and 2.5 parts Soda ash both at the regular concentration, if I switch to Sodium Bicarbonate PH would be super low this time of year)
2. Lower alk (7 dKH). (I'm doing this)
3. Lower calcium (390-420 ppm) (I'm doing this)
4. More diluted and/or slower addition of additives (both calcium and alk). Mag dosing rate is unimportant here. (This may have been the main or root cause initially as I was doing Calcium at double strength but I stopped this about a month ago. I've programmed the DOS to never dose both parts at the same time and added a powerhead where they are dosed in the sump to add dilution. Yes this is a crazy amount of two part but it is a 400 gallon system with 12 130W leds and wall to wall SPS)
5. Normal to high magnesium and phosphate (been keeping Mag >= 1400, PO4 is low so adding some each day to stay above 0.02
6. Allow organics to rise (less GAC, less skimming, less Purigen, etc.) (No GAC on this tank ever, still skimming 24/7 but not an oversized skimmer)
7. Stop dosing for a few days to allow fresh CaCO3 surfaces to get coated with organics/magnesium/phosphate to reduce further precipitation onto them ( crazy high demand SPS tank, if I stop dosing for just a few hours Alk will bottom out fast like maybe 5.0)
Another video for more context
Also all this scrap[ping is adding fine scratches to the tank. About a month ago if I scrape off all the precipitation it could come back as fast as 24 hours, not that amount takes about 2 weeks to get to the state like in the video. Alyway I am trying to stay the corse but open to feedback on what I might be missing.
Based on Randy's advice that I found on here I have been trying this for a few weeks with some comments in blue
The recipe for reduced precipitation is:
1. Lower pH. Switching to bicarbonate will help considerably. (to keep nighttime PH above 7.8 and daytime not higher than around 8.17, I've been dosing 1 part NaOh and 2.5 parts Soda ash both at the regular concentration, if I switch to Sodium Bicarbonate PH would be super low this time of year)
2. Lower alk (7 dKH). (I'm doing this)
3. Lower calcium (390-420 ppm) (I'm doing this)
4. More diluted and/or slower addition of additives (both calcium and alk). Mag dosing rate is unimportant here. (This may have been the main or root cause initially as I was doing Calcium at double strength but I stopped this about a month ago. I've programmed the DOS to never dose both parts at the same time and added a powerhead where they are dosed in the sump to add dilution. Yes this is a crazy amount of two part but it is a 400 gallon system with 12 130W leds and wall to wall SPS)
5. Normal to high magnesium and phosphate (been keeping Mag >= 1400, PO4 is low so adding some each day to stay above 0.02
6. Allow organics to rise (less GAC, less skimming, less Purigen, etc.) (No GAC on this tank ever, still skimming 24/7 but not an oversized skimmer)
7. Stop dosing for a few days to allow fresh CaCO3 surfaces to get coated with organics/magnesium/phosphate to reduce further precipitation onto them ( crazy high demand SPS tank, if I stop dosing for just a few hours Alk will bottom out fast like maybe 5.0)
Another video for more context
Last edited:
