I'm late to the dance, but I want to comment on a couple of posts I've seen concerning DPD powder. Many of you notice the R-870 powder will darken to gray over time and has a tendency to clump. However (assuming you have chlorine in your pool) The solution will turn the same intensity of pink and the result is valid.
If your solution doesn't turn pink simply run the OTO comparator block test........those five drops of R-600 will turn yellow if there is chlorine in your pool The 870 powder turning to gray and clumping bugs us, too but it is the most precise test on the market and that test is essential for the methods we use to manage pools.
We're exploring possibilities for a better test that doesn't increase the cost and we'll keep you posted when we do
If your solution doesn't turn pink simply run the OTO comparator block test........those five drops of R-600 will turn yellow if there is chlorine in your pool The 870 powder turning to gray and clumping bugs us, too but it is the most precise test on the market and that test is essential for the methods we use to manage pools.
We're exploring possibilities for a better test that doesn't increase the cost and we'll keep you posted when we do