KH is a measurement of your waters buffering capacity (hardness)
this sticky I wrote explains it in a little more detail
DKH is Degrees of Carbonate Hardness. It's the measurement unit of KH.
For example, I have 6 DKH - my KH measurement is 6 degrees. The other measurement is ppm I believe.
API makes a supplimentary test kit for their freshwater master kit for measuring Kh and Gh.
I would leave your pH at 6.0, but be aware of what fish you plan to get as they may not like the acidic water. Most fish will adjust perfectly fine to your pH with a slightly longer than usual acclimation.
6 is not too low for guppies, just be sure to monitor your hardness and pH occasionally and keep up with your tank maintenance, as the lower your pH and hardness levels are, the closer your water is to being unstable on the low side. (yes driftwood and etc. lowers your pH)
I use liquid measuring tests for KH, this is the main thing to test for water hardness (buffering)
Something to watch out for......
In my planted tank, I am having an issue where the KH is dropping. When the carbonate hardness is under 4 degrees, the pH becomes unstable. As the KH out of my tap is now measuring 8-10 degrees (it was measuring 2 dKH a few weeks ago), I plan on doing PWC to keep the carbonate levels up so there is plenty for my plants that are consuming it.
If your tank becomes unstable, meaning the KH is below 4, your pH can suddenly drop and stress your fish. As your pH is already 6.0, you would not be able to identify this drop through testing.
I'd recommend purchasing a KH/GH test kit to monitor these levels.....and compare them to your water source levels. You may need to do more water changes or add a component that can raise the KH if necessary.
There really is no magic number other than you need at least 4KH to keep your pH stable.
Definitely pick up a KH/GH testing kit. API offers a combo kit to test both types of hardness that is fairly cheap and accurate.
Potentially, but you need to test to know these levels before taking any action....or....you can end up with a huge mess.
Thank you both for your helps... IT really has helped a lot thnks...
So since my PH is 6.0 then that means that my KH and GH isn't very high... right ??? Low mineral content right ???
Yes this is most likely the case, you can get a kit to test the GH and KH for exact levels but adding crushed coral to raise the KH and pH is not going to do anything drastic to your water... it dissolves very slowly and that's why its considered one of the safe options for altering your KH and pH higher.
I would still get a test kit as it is very useful to know your levels for different conditions (ie you have multiple tank setups / your water source changes / etc.)
To determine true pH you need to add water to a bucket with an airstone. Test the water every 24 hours until the pH remains unchanged. That is your water's pH.
Mine comes out of the tap at 7.2 - 7.6, but my true pH is 6.6 - 6.8.
OK THANKS... THGH my tap water that I add to my water changes are at a PH of 8.0... (a light blue color) So by that my water after water changes are still at 6.0 that means that my Buffer or KH is high... Or is it not... ???
FYI: IM planning on getting the test kit of this saturday...