i'm using a drip system & i'm growing hydroponically out of a closet. I have a 250w light mh & hps, i have been using general hydroponics flora line of nutrients. I always use ordered seeds because would hate to mess up clones. Right now i'm starting over. My last time i grew some white widow seeds. ph was normal in the bloom stage. My ppm i moved up every week little by little while trying to bloom. So over the course of about 10 weeks it went from 700 to 1800 i used florabloom and koolbloom my last time. My light schedule was 12 12 soon as thought they where ready. Before bloom i left the mh on constantly. then i switched to the hps. I hope i didn't leave out any information, Didn't know i would get such quick replies. Thanks so much.
Great description man! For the ph or ppm to move up like that, we have to discover what caused it. ph and ppm affect each other in very exact ratios. Since your ppm was flying up, the ph was equally nuts. Your light is good. No problem there. I use the same nutes. You have to be very careful to mix the nutes outside of the reservoir in an exact size container. I use two gallon, white jugs, (used to hold kitty litter).
The MICRO nutes have to be mixed into the water FIRST. You have to use something with an exact measure. I bought a 50ml graduated beaker for this. Measuring the nutes is very exact because of their potency.
If your drip nozzles are in the light, you need to cover them or slightly bury them to prevent algae buildup around them. That will affect ph slightly.
You haven't said how large your reservoir is. I need to know that. Also, how much water did you add and how often?
This is why:
As your plants use the nutrients from the water, the concentration of the nutrient solution is altered. Either the plant will use more water than nutrients or more nutrients than water and this causes the ph to change either up or down. If you add more nutrient solution to the mix, and the mix is too strong already, several lockouts and overdose can happen. The ph will go nuts. If you add more nutrient solution to an already weak solution, the ph and ppm will start changing and soon become a problem. This is why the nutrient solution needs to be changed out periodically unless you use my method.
My plants use about one gallon of nutrient solution each day during the vegetative cycle, and increasing to two gallons a day during full flower. I have 18 gallons of solution total. Each day, I add one gallon of properly mixed nutes. Each 18 days, (sort of), the entire reservoir has been changed out from a process called "attrition". This keeps my ph right, my nute strength correct and the plants happy.
Each time my plants feed via the pump coming on, my ebb and flow hydro units will fill. The nutrient solution in my reservoir drops to almost the top of the pump before the return line starts the continuous flow. This resolves several things. The solution is thoroughly mixed during each feeding and the solution never becomes uneven in strength. It also aerates very well while running through the grow tubs.
With a drip system, you have a much lesser amount of solution mix. You need to add air stones to your reservoir to make sure the nutrient solution stays well aerated and mixed.
Your entire reservoir contents should be changed out either by attrition or actual removal of the solution within 30 days. If it isn't, you'll have the exact problems you had during your last grow. It sounds like your plants were using too little of the nutrients you were giving them, and the concentration was increasing in your reservoir. This will cause a ppm buildup and a wild ph fluctuation as well as hurting the plants.
The nutrient strength is very important during your grow and will increase as the plants get larger and more full. During their infancy and adolescence, they require less nutrients each day. With Hydroponics, watching how your plants react to the nutrients is half the battle. Whatever reaction you get, you adjust your nutrients to compensate the very same moment. Hydro plants react much faster than soil grown plants usually unless the soil grown plants are root bound.
I'm not sure if that is in fact what happened to you, but it's a guess.
We can all help you with your next grow and see if we can all help you make it a great one!