My tank hits 8.02 during the day, 7.49 at night. I have tried isolating my probes, putting them in different areas of the sump and tank and all readings are consistent. I have a very large skimmer with a line run outside.
Indoor co2 meter shows 688 on one (smaller unit) and a nicer larger unit shows 691... from my understanding these are healthy levels.
My tank's pH was usually 7.61 at night and 8.1 day but the fact that it's been dropping over time has me worried. I do not like negative trends without explanation. I decided to look at the most unreliable equipment in my tank and all signs always point to Neptune stuff. I threw away my probes, bought brand new lab grade apex probes (2) and re-calibrated them with brand new solution. Both probes are within .01 of each other so I am confident they calibrated correctly. When I place them in the solution packets they are 6.9 (7.0) and 9.9 (10.0).
Now, I have two things in my system that lower pH. One is a calcium reactor, a rather large one as my sps load is very high. The tank is 350G volume, lots of SPS colonies and 6 tangs, 2 wrasse, 2 clowns tanks dem: 96x30x24. The reactor is a GEOCR818 with two gallons of ARM extra course. My melting point is lower and pH measured leaving the reactor is 6.4. It barely keeps up at 90ml per min drip (kamoer).
I feel the reactor is dialed in, I set it up with an initial effluent flow rate of 60ml/min and 1 bubble per 6 seconds. Measured effluent DKH at 15, then moved up to 5 bubbles and 65/ml and then eventually getting to micro adjustments to where my DKH was 20 and my bubble rate is 1 bubble per 3.2ish seconds and drip rate is 90. The controller is there to turn off regulator for emergencies but that never happens as it runs 24/7.
Alk is 8.5
Temps 77.8-78.1 consistent
My other piece of equipment is a large sulfur denitrator I used to keep no2 at 2ish. I do not carbon dose. The effluent drips into a DIY aeration chamber with a large air stone. The air pump has an inlet that allows me to pull air directly from outside and it's a powerful air pump. I also have a second airstone in my sump intake chamber just to bring air in. So, that makes 3 different areas I am bringing air in the sump. I know the air stone works because my effluent out of the aeration chamber is 8.2 day and 7.9 night consistent.
I tried the air test:
Indoor test at night: 7.9
Outdoor test at night 8.1
Indoor test day: 8.2
Outdoor test day: 8.4
New salt water in my mixing station stays consistent with above at 8.2 day/7.9 night (in same room as tank).
Why and how can my in tank pH be so freaking low? 7.49 and still dropping slowly over time. At what point does it stop? Nothing is adding up, what in the world of science is happening inside my tank to cause my pH to drop? Fish seems fine? Shrimp/snails seem fine? Acros seem fine? Have I unlocked a new breakthrough in low pH tank health!?! Can I save the great barrier reef?!
Also, my salifert (yuck) pH kit is consistent with my probes also.
Indoor co2 meter shows 688 on one (smaller unit) and a nicer larger unit shows 691... from my understanding these are healthy levels.
My tank's pH was usually 7.61 at night and 8.1 day but the fact that it's been dropping over time has me worried. I do not like negative trends without explanation. I decided to look at the most unreliable equipment in my tank and all signs always point to Neptune stuff. I threw away my probes, bought brand new lab grade apex probes (2) and re-calibrated them with brand new solution. Both probes are within .01 of each other so I am confident they calibrated correctly. When I place them in the solution packets they are 6.9 (7.0) and 9.9 (10.0).
Now, I have two things in my system that lower pH. One is a calcium reactor, a rather large one as my sps load is very high. The tank is 350G volume, lots of SPS colonies and 6 tangs, 2 wrasse, 2 clowns tanks dem: 96x30x24. The reactor is a GEOCR818 with two gallons of ARM extra course. My melting point is lower and pH measured leaving the reactor is 6.4. It barely keeps up at 90ml per min drip (kamoer).
I feel the reactor is dialed in, I set it up with an initial effluent flow rate of 60ml/min and 1 bubble per 6 seconds. Measured effluent DKH at 15, then moved up to 5 bubbles and 65/ml and then eventually getting to micro adjustments to where my DKH was 20 and my bubble rate is 1 bubble per 3.2ish seconds and drip rate is 90. The controller is there to turn off regulator for emergencies but that never happens as it runs 24/7.
Alk is 8.5
Temps 77.8-78.1 consistent
My other piece of equipment is a large sulfur denitrator I used to keep no2 at 2ish. I do not carbon dose. The effluent drips into a DIY aeration chamber with a large air stone. The air pump has an inlet that allows me to pull air directly from outside and it's a powerful air pump. I also have a second airstone in my sump intake chamber just to bring air in. So, that makes 3 different areas I am bringing air in the sump. I know the air stone works because my effluent out of the aeration chamber is 8.2 day and 7.9 night consistent.
I tried the air test:
Indoor test at night: 7.9
Outdoor test at night 8.1
Indoor test day: 8.2
Outdoor test day: 8.4
New salt water in my mixing station stays consistent with above at 8.2 day/7.9 night (in same room as tank).
Why and how can my in tank pH be so freaking low? 7.49 and still dropping slowly over time. At what point does it stop? Nothing is adding up, what in the world of science is happening inside my tank to cause my pH to drop? Fish seems fine? Shrimp/snails seem fine? Acros seem fine? Have I unlocked a new breakthrough in low pH tank health!?! Can I save the great barrier reef?!
Also, my salifert (yuck) pH kit is consistent with my probes also.
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