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View Full Version : High nitrates a problem for plants?



eddiemigue
08-03-2013, 05:06 AM
I have read much about the need to start with plants that don't have high nutrient requirements until the system matures, but I haven't seen anything on whether high nitrates cause problems for plants. As I have been reworking my system to account for temp, humidity and indoor lighting requirements, I have been running without plants (only duckweed) for a couple of weeks. Also, the nitrates in my system have been >100ppm since soon after introducing the fish and have not come down since.

I expect to add a bunch of greens shortly, but these have been recently sown, and I wonder whether placing them in water with very high nitrates will cause damage/stunted growth. Will the leaves become too succulant and thus more prone to disease? Should I do a major water change just prior to adding plants?

I have had decent success with growing outdoors in soil, but AP growing in my garage has thus far eluded me. Fish are fine, but plants have underperformed, and I wanted to avoid another round of dissapointments.

Oliver
08-04-2013, 12:23 AM
I am curious as to what your pH reading is.

I have noticed that when we harvest too many plants and there is a lag time before the next batch gets going, the pH starts dropping and it is hard to keep it up by adding pH-Up. As soon as we get the new plants growing the pH starts going back up. Not sure of the mechanism that causes this but we have observed it several times.

Oliver

JCO
08-04-2013, 12:48 AM
I would not be as worried about high nitrates as I would the amount of lighting the plants are receiving. Plants will grow in a glass of water if they get the right amount of light and they will uptake only the amount of natural nutrients they need and the rest will be bypassed. Plant your veggies and pay particular attention to the lighting...keep it close to the plants and raise it as they grow. :mrgreen:

eddiemigue
08-04-2013, 04:25 AM
Ph has tended to stabilize around 6.8, but I haven't checked too recently and will take another measurement. Glad to hear that the plants should be fine. Once I setup the GB's, lighting, and check ph, I will post an update.

Thanks both.

JCO
08-04-2013, 10:04 AM
Photos please :mrgreen: