I cut six 4-inch-diameter circles in the top. I grew my plants in soil first until they put out their first set of true leaves. Then I placed them in 4-inch-diameter plastic cups with many holes cut at the bottom.
They are filled with lava rock/gravel mixture. The airstones bubble directly beneath the cups so the air enters the cups and supplies oxygen to the roots.
Recently I switched from liquid Miracle-Gro? to Peters 20-20-20 with micro-nutrients?. The liquid Miracle-Gro promoted algae growth and turned the reservoir brown, With the Peters solution the water stays blue with no algae.
After 5 days, the plants' roots have grown rapidly and are as white as paper. Is the Peters brand good or is there a better food out there that I have not come across?
Peters fertilizer is usually used for fertigation (watering a plant in a non-nutritive planting mix with a water-nutrient solution). It's very similar to hydroponics. Most of these peat moss or forest product mixes contain added lime to supply calcium.
The powdered fertilizer dissolves easily in water. It's fed through capillar y mat irrigation, ebb and flow, or watered by hand or overhead. The fertilizer contains all the nutrients needed for hydroponic cultivation with the exception of calcium, which is found in many commercial planting mixes. Calcium is essential for plant growth. Without it growth stops and leaf necrosis occurs.
Most hydroponic gardeners use specially formulated hydroponic fertilizers found in many indoor grow shops. If you are having success with Peters there is no reason not to use it. If you continue, you should add a water-soluble calcium-rich fertilizer such as one of the cal-mag formulations to the water-nutrient solution.
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