Low Ph And High Kh

[dave_m13]

Hi All

I have just tested my 54 litre tank to see how much CO2 is being added by my Nutrafin CO2 system and I have had some strange readings.

The PH I worked out to be 6.4 to 6.6 cannot tell for certain what one it is, then the KH test came out as 110ppm. Now if I worked this out on a CO2 calculation and the PH was 6.5 I would have an extremely large amount of CO2 present in the tank, 56ppm according to PFK. If I did have this amount I think this would be have major affects on the fish but the fish are fine.

Do you think that there is something wrong with the tester or something else, I did a test using the same tester (Nutrafin KH and GH) on the large tank and it came out as 70ppm with similar PH.

Thanks
Dave

 

[Themuleous]

Have a read of this thread and this thread, that should explain things better.

I would add that (and we all have this so I'm not having a go, just explaining ) if you take a conservative approach to those readings you gave, you could have a pH of 6.6 and a kH of 101ppm, which would give you 45ppm CO2. If you took the other side you could have a pH of 6.4 and KH of 119ppm, which gives a CO2 of 80ppm. What Im basically saying is that test kits are not accurate enough to give you secure readings, so providing the fish are not gasping at the surface then keep the CO2 level high, its better to be over 30ppm than under IMO.

All that said give the 1 pH point test a try and see what result you get, its not 100% accurate but should give you a better feel for how your CO2 levels are doing

Sam

PS - according to those CO2 charts my CO2 is at 114ppm! (fish are fine BTW) but I sure its the inaccuracy of the test kits making it that high rather than it actually being that high