tiptoptank said:
So first off I have really hard tap water.
kh of about 10. But the second I add it to my tank It goes to about 3 or sometimes 2. Now I have a presurised c02 and was wondering if the co2 acually removes the carbonates
The short answer is no,
CO2 does not remove carbonate/bicarbonate. We depend on this unique relationship of
CO2 and carbonate based buffers to determine the amount of
CO2 dissolved in water. An exact known quantity of carbonic acid forms when
CO2 is dissolved in water. Carbonic acid lowers pH. The amount of the drop in pH while the
KH remains stable is what allows us to determine
CO2 levels. Once
CO2 injection is removed the pH will rise again while the
KH remains unchanged until the amount of
CO2 is roughly equal to atmospheric equilibrium.
CO2 moves freely into and out of solution while leaving the "
KH" unchanged.
TG, I'm not sure, in this case, we could associate the loss of
KH with that of lowered phosphate levels. His beginning
KH was approximately 180
ppm...the drop was to 40-50
ppm...this would equate to a beginning phosphate level of (180-50) 130
ppm of phosphate...can you imagine the algae problems in a tank with 130
ppm of phosphate? Even under ideal conditions with a huge plant mass it would take quite a few months to chew threw that much phosphate.
My best guess would be that another acid is present and causing two problems. The first is a test kit interference. The second is to actually consume the buffer in the change water.
To get to the root cause of a problem like this requires a step by step process of elimination diagnosis. Could you describe all the hardscape (rocks, driftwood, substrate, etc.) in your tank in as much detail as possible including where you got the materials? And, is you source water from a well or is it a municipal water utility? Thanks for the additional information. While I know this may seem troubling to you, the solution once the cause is determined should be quite simple...and we all will gain experience and knowledge as we figure out the problem together.
And lastly, what is the pH and
KH of your water directly out of the tap, and then that same water left out for 24 hours...not put in your tank just left in a bowl?