Dear family and friends quick check on results after approx 18 months . Final verdict will be in December this year.
So far vivid petite plus 20% of copper powder is the best vivid petite can get (the middle black sample vs original petite left sample)
The absolute winner is Altex 5 plus with 5% zinc (znpt) not zinc oxide, 10% copper sulphate and 10% paint any mould additive ( here in blue).

Modified Altex has no slime after 18 months sitting in the water. I am speechless .