Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
I figure these just a bit differently, but get the same results, the same concept:
1) Figure out how much fertilizer all my tanks will use in one week.
2) Figure out how much volume I want to dose each day. For me, I need a way to quickly figure out how to dose many different sized tanks. I choose to dose @ 1ml per 3 gallons of tank volume.
This means I can walk up to each tank with a syringe in hand and think "OK, 15 gallon tank, squirt in 5 ml.... OK, 45 gallon tank, squirt in 15 ml... OK 10 gallon tank, squirt in 3 ml" and so on.
3) Multiply out all that I need to dose all my tanks for a week comes out to 1000 ml. I actually mix up 2 weeks worth at a time, so I make 2 liters of Macros and 2 liters of Micros.
a) I add the 2 weeks worth of KNO3, KH2PO4 and K2SO4 to the Macros bottle, and CSM+B and chelated Iron to the Micros bottle.
b) Add Excel to both bottles. So, when I dose any fertilizer the tank is also getting the daily dose of Excel.
c) Top off with distilled water.
The actual amounts of each fertilizer have changed as I change my maintenance schedule and the livestock level in the tanks. But even when I have to add the highest level of fertilizers the amounts are easily dissolved in the water.
I have adjusted the dosing levels, too. For a while I was dosing 1ml of mix per 1 gallon of tank volume. Then I tripled the concentration of ferts, so cut the dosing to 1/3 as much.