MiracleGro and Macronutrients
**Edited to move my question up-front**
Question: How long can I expect MiracleGro to continue providing N, P & K to the plants after the initial set-up? Is it a matter of days, weeks or months? I'm particularly concerned with K since it's not coming in through fish food. Details about my tank are below...
I've effectively been talked down from the nutrient test kit rail (had I known the K test kit alone was $45 it would've been a non-starter anyway).
I just set up a low-tech tank ~ 3 weeks ago. Here are some of the particulars:
(2) 6700k 54w Tek T5 bulbs with window screen to reduce PAR by an estimated 40% (per experiments done by Hoppy)
1 inch MiracleGro Organic Potting Soil Mix
2 inches Eco-complete
10 red jungle vals, 4 brazilian pennywort, 4 bacopa carolinia, 4 red myrio, 3 swords, 3 microswords, 3 floating water sprite, 1 banana plant and one other plant i forget the name of but it's a leafy stem plant
Temp: ~75 degrees
NH3/4: 0.00 ppm
NO2: 0.25 ppm
NO3: 20.0 ppm
PO4: 5.0 ppm
In addition to daily doses of NH4Cl, I've been throwing in some fish food to get the NH3/4 up. I might see a brief spike ammonia, but then it goes to nitrite pretty quickly and that's why I have that 0.25 ppm usually within an hour of dosing the ammonium chloride, and then the nitrite dissipates within a couple more hours.
I'm assuming that in addition to the ammonium chloride and fish food, I'm getting nitrates from the soil. I'm also assuming that phosphate is coming from the soil, and to a lesser extent from the fish food.
Last edited by bikinibottom; 12-12-2012 at 08:02 PM.
Reason: re-organized post