This thread is only about EBB N FLOW with ROCKWOOL chemistry. Its not about drip and rockwool so if thats what you do then please start another thread unless you have interesting data about our situation. If you have some hybrid that might be interesting. If u use another media with ebb n flow that is fine.
So I have been doing ebb n flow with hugos - 6 inch rockwool cubes for a long time. Mostly works great tho in summer some problems occur. We use Flora Nova nutes 1 part and keep PPM about 1200 =/1 200 with 0.5 scale. pH around 5.8. Water in flower 3 times a day. Water in Veg once a day unless big bushes in veg where we go 2x/day. Pretty textbook standard I think.
Special ordered a sampling syringe that is dwsigned for rockwool sampling from hydro store. The initial results are mind boggling!
As the plants get older they start to get insane PPM and pH numbers in SOME of the cubes. First of all, when temps are cool and plants look healthy, they can get to 1800 ppm and ph 5.4. Pretty close. When the plants get older and bigger in summer tho, the cubes can get easily to 2000 ppm and 5.2. Right near harvesting before flushing the cubes can get to 4000 ppm. Sick plants can be pH 4.2!
My teheory is the following. In winter plants dont transpire as much using less water and so the cubes salt concentration stays similar to nutrient resevoir. In summer however, water gets used very quickly, especially just before next watering. The ppm might get up to 3000 routinely. this damages roots which cause them to die and also to allow root rot to set in. this causes pH to drop dramatically.
I know many of you will talk about other methods, but this is what i use rockwool, and I love it, its easy and delivers most of the time.
This syringe thing tho blows my mind. The cubes are VERY different from the nutrient. I know this stresses plants sometimes. I have seen NOTHING mentioned anywhere about this kind of thing. I bet 99% of people are measuring resevoir nutes and thinking thats the whole story. Its NOT. Thats like measuring the hospital room but not the tempof the patient.
Summary: Early on in veg, ph and PPM dont change much, later on in flower each week more stuff builds up such that by late flower PPM might be double or triple the resevoir.
There is probably the drawback to rockwool in ebb n flow, why its not used much professionally. But my hydro store sells soooooo much of it, its gotta be used by tons of ya. Admit it.
Also in hot weather cubes use up water fast so before next watering not much weight left in cube.
We normally add fresh tap water over cubes every 3 weeks now. When cubes are salt filled after 2-3 weeks and you add new water over them they can raise 40 gal res by 200 ppm. Thats say 6 plants releasing so much dried up nutrient that it raises PPM 200 PPM.
Anybody else use syringe? Get one, 10 bucks! sample and pour in shot glass and mesure with hanna pen. easy. Get crazy results.
Some variables include: air temp, res temp, aerating water, H202, beneficials, depth of rockwool submersion, numbers of watering per day, duration of waterin per day, rinsing, flushing, etc.
I find this to be amazing, its like think you are providing healthy food to your family only to find out they have been gorging on McDonalds in secret. And just like America is filled with overweight pigs from nasty food, our girls are not getting what I want them to!
I will even provide the hydrofarm part number (hope this dont mess up post, its a 12 buck combo, im not shillin for nobody) AD207079 - 60cc syringe, AD207057 - metal needle
I can add more to this thread as I find out but I urge you to get the syringe and try this. Post your results up here.
So I have been doing ebb n flow with hugos - 6 inch rockwool cubes for a long time. Mostly works great tho in summer some problems occur. We use Flora Nova nutes 1 part and keep PPM about 1200 =/1 200 with 0.5 scale. pH around 5.8. Water in flower 3 times a day. Water in Veg once a day unless big bushes in veg where we go 2x/day. Pretty textbook standard I think.
Special ordered a sampling syringe that is dwsigned for rockwool sampling from hydro store. The initial results are mind boggling!
As the plants get older they start to get insane PPM and pH numbers in SOME of the cubes. First of all, when temps are cool and plants look healthy, they can get to 1800 ppm and ph 5.4. Pretty close. When the plants get older and bigger in summer tho, the cubes can get easily to 2000 ppm and 5.2. Right near harvesting before flushing the cubes can get to 4000 ppm. Sick plants can be pH 4.2!
My teheory is the following. In winter plants dont transpire as much using less water and so the cubes salt concentration stays similar to nutrient resevoir. In summer however, water gets used very quickly, especially just before next watering. The ppm might get up to 3000 routinely. this damages roots which cause them to die and also to allow root rot to set in. this causes pH to drop dramatically.
I know many of you will talk about other methods, but this is what i use rockwool, and I love it, its easy and delivers most of the time.
This syringe thing tho blows my mind. The cubes are VERY different from the nutrient. I know this stresses plants sometimes. I have seen NOTHING mentioned anywhere about this kind of thing. I bet 99% of people are measuring resevoir nutes and thinking thats the whole story. Its NOT. Thats like measuring the hospital room but not the tempof the patient.
Summary: Early on in veg, ph and PPM dont change much, later on in flower each week more stuff builds up such that by late flower PPM might be double or triple the resevoir.
There is probably the drawback to rockwool in ebb n flow, why its not used much professionally. But my hydro store sells soooooo much of it, its gotta be used by tons of ya. Admit it.
Also in hot weather cubes use up water fast so before next watering not much weight left in cube.
We normally add fresh tap water over cubes every 3 weeks now. When cubes are salt filled after 2-3 weeks and you add new water over them they can raise 40 gal res by 200 ppm. Thats say 6 plants releasing so much dried up nutrient that it raises PPM 200 PPM.
Anybody else use syringe? Get one, 10 bucks! sample and pour in shot glass and mesure with hanna pen. easy. Get crazy results.
Some variables include: air temp, res temp, aerating water, H202, beneficials, depth of rockwool submersion, numbers of watering per day, duration of waterin per day, rinsing, flushing, etc.
I find this to be amazing, its like think you are providing healthy food to your family only to find out they have been gorging on McDonalds in secret. And just like America is filled with overweight pigs from nasty food, our girls are not getting what I want them to!
I will even provide the hydrofarm part number (hope this dont mess up post, its a 12 buck combo, im not shillin for nobody) AD207079 - 60cc syringe, AD207057 - metal needle
I can add more to this thread as I find out but I urge you to get the syringe and try this. Post your results up here.
