"Thanks for the suggestions--they have helped a lot. We have real acidic water, so it's not likely calcuim. I've had slime (bacterial?) in other lines, but I've been able to flush that out by hand. It's the…"
"I have come across this before I am quite sure what you are seeing is calcium build up.. It is either coming from your water source or perhaps the fertilizer you are using in your water... run some vinegar through all the drippers, that should clear…"
"Even the best drip system needs regular maintance of the drippers. Do you have a filter on the water coming into the line? If not you need one and it needs to be check regularly. That will help eleminate the sand and other particulates that often…"
"First I would install flush valves on the ends of your drip lines, These valves are open when the water pressure is under 2 lbs. When the pressure increases the valve closes. Install your drip lines so they will drain towards the…"
"Zerotol might remove some but if it's as bad as I envision your going to probably need something more aggressive. I guess it really depends on how many drippers were talking about and how easy it is to pull all the drippers away from the…"