First post (recent lurker), thanks for checking this out and offering any solutions!
Issue: Soil pH levels have steadily decreased from 6.3pH range to as low as 5.4-5.5pH.
Background: Recently installed an automated irrigation system for my 4x4 grow tent this past Sunday (5 days ago). Simply made up of a 17gal reservoir (storage bin) with a main line pump and an aeration/mix pump. From day one of the new system, I have added in regular tap water to refill the reservoir to about 14gals every day in the morning before any irrigations occur. Once tap water is replenished in reservoir, I add my nutrient regiment based on the total number of gallons of tap water I used for the refill. This means that each consecutive day of operation, it is the same mixture that has been in the tank from the previous days regiment. I just top it off every morning with a correlated amount of nutrients and water, which then gets balanced out to 6.3-6.5pH.
Concern: Why would my soil pH (based on runoff tests) be getting lower and lower by the day? My ppm and EC have risen also by the day, however I am personally choosing to push slightly higher numbers in my grow environment. Could my total volume of irrigations throughout the day be a contributing factor? Or is it leaning more towards residual nutrients being mixed in with newer nutrients every morning?
Grow Medium: 5 gallon fabric pots, Drain Away Trays (runoff), 3/4" main irrigation line with 1/2" lines leading to 3 dripper emitters per plant.
Irrigation Schedule: I use a very rudimentary and not super accurate "crop steering" irrigation schedule. First irrigation event 2 hours after lights on. Total of 6 irrigation events over 1.5 hours, with each event every 15 minutes for a shot size of 300mL each. This is to saturate the soil after overnight dry-backs and to reach (roughly estimated) Water Capacity with runoff. I also spread out 3 Maintenance Shots of 500mL each throughout the remaining time of the light cycle, with the last of those maintenance shots ending 2 hours before lights off. This is then repeated for the next day after Reservoir has been refilled with an appropriate balance of nutrients and tap water. Important Detail: My aeration/mixing pump turns on 30 minutes before each irrigation event to stir the nutrients and water around before sending it out to the plants. The math for the total water given to each plant (Week 1 of Flowering) to be about 3300mL (right under a gallon per plant if estimates are correct).
Someone has mentioned that it could be from old nutrients mixing with newer nutrients every day, leading to pH drops, but it doesn't make sense that why that would happen if I balance the pH with pH down after refilling the reservoir every morning. I speculate its the 9 irrigation events that I am giving it throughout the day, but no other data to back that up at this moment. Should I just flush and restart? Or is there something I am doing incorrect, which can be fixed?
Reaching out because I am new to automated irrigation systems and have never experienced this steady decrease in pH runoff levels over the course of 5 days. Any suggestions and opinions would be appreciated. Thank you for all the knowledge you guys post on here.
Issue: Soil pH levels have steadily decreased from 6.3pH range to as low as 5.4-5.5pH.
Background: Recently installed an automated irrigation system for my 4x4 grow tent this past Sunday (5 days ago). Simply made up of a 17gal reservoir (storage bin) with a main line pump and an aeration/mix pump. From day one of the new system, I have added in regular tap water to refill the reservoir to about 14gals every day in the morning before any irrigations occur. Once tap water is replenished in reservoir, I add my nutrient regiment based on the total number of gallons of tap water I used for the refill. This means that each consecutive day of operation, it is the same mixture that has been in the tank from the previous days regiment. I just top it off every morning with a correlated amount of nutrients and water, which then gets balanced out to 6.3-6.5pH.
Concern: Why would my soil pH (based on runoff tests) be getting lower and lower by the day? My ppm and EC have risen also by the day, however I am personally choosing to push slightly higher numbers in my grow environment. Could my total volume of irrigations throughout the day be a contributing factor? Or is it leaning more towards residual nutrients being mixed in with newer nutrients every morning?
Grow Medium: 5 gallon fabric pots, Drain Away Trays (runoff), 3/4" main irrigation line with 1/2" lines leading to 3 dripper emitters per plant.
Irrigation Schedule: I use a very rudimentary and not super accurate "crop steering" irrigation schedule. First irrigation event 2 hours after lights on. Total of 6 irrigation events over 1.5 hours, with each event every 15 minutes for a shot size of 300mL each. This is to saturate the soil after overnight dry-backs and to reach (roughly estimated) Water Capacity with runoff. I also spread out 3 Maintenance Shots of 500mL each throughout the remaining time of the light cycle, with the last of those maintenance shots ending 2 hours before lights off. This is then repeated for the next day after Reservoir has been refilled with an appropriate balance of nutrients and tap water. Important Detail: My aeration/mixing pump turns on 30 minutes before each irrigation event to stir the nutrients and water around before sending it out to the plants. The math for the total water given to each plant (Week 1 of Flowering) to be about 3300mL (right under a gallon per plant if estimates are correct).
Someone has mentioned that it could be from old nutrients mixing with newer nutrients every day, leading to pH drops, but it doesn't make sense that why that would happen if I balance the pH with pH down after refilling the reservoir every morning. I speculate its the 9 irrigation events that I am giving it throughout the day, but no other data to back that up at this moment. Should I just flush and restart? Or is there something I am doing incorrect, which can be fixed?
Reaching out because I am new to automated irrigation systems and have never experienced this steady decrease in pH runoff levels over the course of 5 days. Any suggestions and opinions would be appreciated. Thank you for all the knowledge you guys post on here.
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