Now then if the ph in the tank this one in 6.2 more than likely is q the kh 5, do not be a real reading, perhaps rather be kh2, in any case comprare a test of co2, I have a good chance to eheim's test.
I check with the distilled- water and sodium bicarbonate mixture ( kh4 ), does result be probably green color or lightly yellow to be the co2 ok??

.Another doubt that I have is the following, if I fulfill the permanent test with distilled water kh4 and the tank's water is REAL kh 2, a ph 6.2 like I have serious ideal and the mixture of kh4 the tank acquires a color giving a lot of co2 to contain a kh ( 4 ) q itself really he does not have . is This possible???
Excuse translation no himself if what I attempt saying gets along well .

Regads..