As a follow up to your 2nd question...
The filter is a 3 step filter, 1st a sponge/filter floss, 2. carbon filter, 3. "biomax" looks like zeolites, it claims this part reduces ammonia and nitrate.
my ammonia tests show 0-0.25ppm ammonia...
My tests are 7.4 ph, 0-0.25ppm ammonia, 5+ ppm...