new to the forum been growing a while now but ran into an issue my cloning is failing I have been using the deep water method with air stones it has worked good in the past with 80% the problem has been I get a muchus build up on my stem down in the water let say I am using well water that is hard water I use PH down because my water is about 7.4 PH , but this time I used distilled water and had same problem any suggestions