Yes, and my color changes are the same as yours. If I run the test twice in a row, I have to admit the second time I add 5, swirl, add 5 swirl, add 5 swirl, then drop by drop. I just ran it again, drop by drop, and it is 200. Drat, I don't know what the problem is. I just tested the pH also, 1-1/2 hours after adding 3/4G MA, and it is down to 7.0. I will let MA circulate a half hour more and then aerate again. When pH comes up I will test TA again.