LOW KH

Using a JBL testing kit and water is changing colors as soon as i add the second drop:

1st drop => water turns blue
2nd drop => water turns yellow/orange

Would that correspond to 1 degree German scale?
If it is then i believe it is too low, is it?
finally, considering i keep Discus only in that tank, what is the best way to fix that?

Thank you

Im in the same situation. Very soft tap water causing low buffering in my tanks and low ph under 6. Ive used coral sand, 20 kilos in 1300l water with 1 deg rise in KH using Sera test kit.

I am not comfortable with my PH tests. Dont get me wrong none of them points out to an extreme. I have been using:

- API 5 in 1 test strips (finished them so wont be using again) - all my tanks around 7
- Some japanese orange test strips (very distinctive colours) - always around 7
- JBL 3 to 10 PH reagent ==> less comfortable with that one as i don't see a clear difference to point towards 6.5 or 8 (i may be colour blind . I am thinking of buying an electrode PH tester.

My 116L Discus which is the only one i really worry much about is bare bottom for over a week, gets 18L changed on a bad day and 36L on a normal day treated with PRIME from SEACHEM (to detoxify nitrites). KH is showing low but as I mentioned PH seems quite steady: I haven't seen extreme figures. Should i do something about this though?Tank not fully cycled.

Ive never kept discus but from what I know they like soft water low kh and low ph maybe 6. Im confused as to why you doing large daily water changes and adding prime if the tank is still cycling as it needs nitrites and ammonia to establish a bacteria colony.

If there is a query on whether the pH is 6.5 or 8 then a new system is needed as the free acid concentration at pH 6.5 is 32 times greater than that at pH 8…..that is an awful lot.

Maybe an electronic pH tester is better…..but maybe not as they need calibrating often and still give mad off-the-rails results if not used correctly. But at least you don’t need the special daylight and good eyesight

Water conditioners such as Prime should be used to dechlorinate and condition the tap water.
They should not be used to remove nitrogenous waste from the tank, even though the ability to remove nitrogenous waste from the conditioned water is of benefit where chloramines are used in the tap water.

As for the KH, it is what you do with that low reading that is important as opposed to just having a low reading.

In another thread I commented on a question on when is best time to do water tests…..in that I mentioned about lighting: in a tank with good lighting, active plant life and a low pH buffering capacity you may find that pH can rocket from low to high very rapidly when you have some carbonate in the low KH water with high photosynthetic activity plants.
With a low KH, as the biological filters kick in and start working at high capacity then you will have the potential of the pH crashing due to all the nitrous acid and nitric acid being produced by the biological filters and not neutralised.

These problems are quite common in Discus tanks where owners have tried to lower the KH and pH too much without taking into consideration much more important water parameters (in fact, when it comes to Discus pH and KH are pretty low on the water quality importance list)

Ian