1. How big is your tank?
375l, 325l, 360l

2. how much light do you have?
300W HQI, 216W T5, 150W HGI

3. How many and what type of fish do you have?
Some fish but no much.

4. Is your tank heavily planted?
All tanks all planted tank.

http://www.republika.pl/andkoni/akwarium4.jpg
http://www.republika.pl/andkoni/akwarium6.jpg

I need help with configure Ro water to my requirements.
In first tank i give 15 ppm K and 5mg in change water but in tank 3 with 150
Hqi 90*90*45 is toomuch and i have alges-cyjanobacter.