Hi.
I was having some BBA that I couldn't get rid of. After increasing micros dosing I saw some improvement on eleocharis but then BBA started expanding. So then I thought it could be a CO2 problem afterall.
I have a cheap PH controller that seems to be doing a good job, calibrated with reference solutions and checked with a JBL test. I've started increasing CO2 and seeing PH decrease to levels that one year ago would have made my fish gasp. So I immediately thought something else should have changed.
I've measured KH of my tap water with a JBL test kit and it reads 6 dKh (maybe a bit less since it shortly changed color for a second after the 5th drop). I think this hasn't changed, or not much, but I remember PH being around 8 and now is 7.2. I regret not having registered tap water parameters over time.
Anyway, now I can lower my tank PH to 6.1 while I used to maintain it at 6.25 because fish would start gasping when under 6.2. And I don't think water is now more oxygenated than it was before. I don't know what exactly has changed and whether this change will last.
If I trust the KH/PH/CO2 table, seeing that my tap water PH is 7.2 and that normal CO2 levels are 2-3ppm, I should have around 1.5 KH. And that would explain that I can get to PH 6.1.
I've read about KH not being the same as carbonate hardness. I'm confused about this comment. It would imply that the KH/PH/CO2 table uses carbonate hardness, not KH.
If I've understood well that carbonate hardness must be lower than KH and it's the former that affects the relationship PH/CO2, then my carbonate hardness could be 1.5 and my KH 6. I wonder where the tap water KH comes from. Phosphates?
Since I'm using a PH regulator to avoid killing my fish, I don't know anymore which target PH is safe to use in the long term. My carbonate hardness could change again and I would only notice because of algae or fish dying. How else could I know when my tap water carbonate hardness changes? I only know about KH tests.
This could be related. My city has a water treatment plant with reversible hydrolysis and it seems carbon filtration has been added lately. Our water sources have high nitrates, fertilizer and pesticidal residues.
UPDATE: KH of my tank water is 7.
I was having some BBA that I couldn't get rid of. After increasing micros dosing I saw some improvement on eleocharis but then BBA started expanding. So then I thought it could be a CO2 problem afterall.
I have a cheap PH controller that seems to be doing a good job, calibrated with reference solutions and checked with a JBL test. I've started increasing CO2 and seeing PH decrease to levels that one year ago would have made my fish gasp. So I immediately thought something else should have changed.
I've measured KH of my tap water with a JBL test kit and it reads 6 dKh (maybe a bit less since it shortly changed color for a second after the 5th drop). I think this hasn't changed, or not much, but I remember PH being around 8 and now is 7.2. I regret not having registered tap water parameters over time.
Anyway, now I can lower my tank PH to 6.1 while I used to maintain it at 6.25 because fish would start gasping when under 6.2. And I don't think water is now more oxygenated than it was before. I don't know what exactly has changed and whether this change will last.
If I trust the KH/PH/CO2 table, seeing that my tap water PH is 7.2 and that normal CO2 levels are 2-3ppm, I should have around 1.5 KH. And that would explain that I can get to PH 6.1.
I've read about KH not being the same as carbonate hardness. I'm confused about this comment. It would imply that the KH/PH/CO2 table uses carbonate hardness, not KH.
If I've understood well that carbonate hardness must be lower than KH and it's the former that affects the relationship PH/CO2, then my carbonate hardness could be 1.5 and my KH 6. I wonder where the tap water KH comes from. Phosphates?
Since I'm using a PH regulator to avoid killing my fish, I don't know anymore which target PH is safe to use in the long term. My carbonate hardness could change again and I would only notice because of algae or fish dying. How else could I know when my tap water carbonate hardness changes? I only know about KH tests.
This could be related. My city has a water treatment plant with reversible hydrolysis and it seems carbon filtration has been added lately. Our water sources have high nitrates, fertilizer and pesticidal residues.
UPDATE: KH of my tank water is 7.
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