ELSO CA Testing question

[cav~firez22]

I use this kit, and i usually only test the appox, as i have figured out that with my tank, i can take the approx, and subtract 20 - 30 from the results, and that gives me the same reading as doing the accurate test. i did them both 4 times (over a 4 week period) and my theory worked out well for me.

So now i just do the appox, and if it reads 480 - 500, im ok.

hope that helps a little