Not everybody has irrigation water with high alkalinity. In one study from Michigan State University, about 30 percent of the irrigation water tested had alkalinity levels below 40 ppm without any acidification. Even in areas where high alkalinity is considered normal, some growers have switched to low alkalinity sources such as reverse osmosis purified water or rain water.
The primary problem associated with low alkalinity water is a tendency for substrate pH to drop over time, which can cause micronutrient toxicity problems (Figure 3). Low media pH problems are often a result of fertilizer selection. Fertilizers high in ammoniacal nitrogen are acidic, and without any alkalinity in the water to balance the reaction (resist lowering of pH), acidic fertilizers will tend to drive the substrate pH down over time.....
There is the answer... You needed to mix in that 5 gal bucket some ca...
then ph it to 6,
then slowly add it to the system.
let it go 24 hrs and pull a 5 gal bucket from the system, and adjust ph in the bucket to 6.
repeat till at 5.8 or what ever you was shooting for...
Always add it back slow as the water is circulated so fast that rapid changes in ph can shock the plants from what I have read...
I even got an email from a person that had run the UC and he said, for what this is worth, if when adjusting the ph down I over shot my mark, that I had to dump the res and start over. He said not to use ph up.
I really dont know why this is and I havent had time to google and find anybody to substantiate these claims...
But I thought I would add that here.. Have NO IDEA if they is any truth in that..
As much as we know, he might not know shit, and thats why he sold me his UC system after 4 months :)
He did say in his email when i asked him why he was selling it, he said he got caught up in the hype, and that he had a family and realized he was being very stupid...
So I doubt he had very much knowledge of the UC system...
I guess I can always bug CC for the answers lol...