I've had a Salifert CA test for over a year. It expires 2/22. I had a coral suddenly bleach out and discovered my CA was at 250. My doser container was empty.
So I started raising it slowly over a week. I got it up to 350, but decided to buy a new test. The new one expires in 2025. They have reformulated it, eliminating one liquid. Instead of 8 drops of a solution you immediately put in .6ml of your titrating solution. You get a color change and continue to titrate till the color changes back with the last .4ml. The new reading is 440. I repeated the test with the older kit, 350.
I now doubt both.
So I started raising it slowly over a week. I got it up to 350, but decided to buy a new test. The new one expires in 2025. They have reformulated it, eliminating one liquid. Instead of 8 drops of a solution you immediately put in .6ml of your titrating solution. You get a color change and continue to titrate till the color changes back with the last .4ml. The new reading is 440. I repeated the test with the older kit, 350.
I now doubt both.