I'm having a problem, and so far everything I've tried has been only maybe slightly helpful or made things worse. And I'm all over the map with trying to find a solution-- I don't know if it's pH, overfert, underfert, salt buildup, etc. I'll give the facts and hopefully you fine people will help me 
I'm not using the most sophisticated measuring equipment, and I'm probably going to change to tomorrow, so I may have better data by then as well.
The clones are grown hydroponically in a little cloning box I made... and no problems there. Generally no problems until about 3-4 weeks into flowering, and problems seem to be more intense on some plants vs others, even though they all get the same feeding water.
I've harvested several plants already, and my yields are definitely low, but the bud is still good. Since I've harvested, I've been able to check out the root systems, and they seemed kind of week but I don't know exactly what to look for since I've historically grown hydro. Everything is climate controlled, and I'm using C02.
Tapwater - I'm told Denver's tapwater is fairly hard but I have no way of really knowing the mineral levels. Using pH drops, test between 7.5 and 8.
Feeding Water - Added to tapwater, 3tsp/gal GH florabloom, 2tsp/gal GH floramicro, 1tsp/gal GH floragro, 1tsp/gal botanicare vitamino, 1tsp/gal rock supercharge, 1tsp/gal rock resinator, 1tsp/gal GH cal-mag
Feeding Water pH - 6-6.5
Watering - Feed until water flows from bottom, runoff is collected below raised platform
Runoff pH - 6
Feeding Frequency - Once a week, tapwater in between if necessary
Substrate - Sunshine Growing Mix #4, 2 gallon pots
Light - 400W HPS, ~1.75 feet from top of canopy
Day C02 - 1400-1700ppm
Day Temp - 80-84
Night Temp - 76-80
Relative Humidity - 55%
Observations: In between fertilizations when flushing with plain tapwater, symptoms progress more quickly. Immediately after fertilization, symptoms progress more quickly. It's almost like no matter what I feed with, it makes things worse. I've checked for mites, definitely aren't any bugs. It's so confusing because it's like if I cut all feeding nothing really improves, but if I feed normally things get worse. I also was adjusting my pH before I started adding cal-mag to more of a 6.5-7, versus what it is naturally after nutes more of a 6-6.5, and this actually seemed to have the worst effect. Adding the cal-mag and not adjusting my pH has slowed the symptoms, but still has clearly not fixed the problem. Lately it seems like the leaves have stopped browning, and started yellowing.
Picture 1 - Most recent, brown spots stop progressing, leaves are becoming more yellow though.
Picture 2 - Brown spots
Picture 3 - Middle tier leaves seem affected more than bottom and top. Small, inner leaves are virtually unaffected.
Let me know if you have any questions guys, I really really appreciate your help!
I'm not using the most sophisticated measuring equipment, and I'm probably going to change to tomorrow, so I may have better data by then as well.The clones are grown hydroponically in a little cloning box I made... and no problems there. Generally no problems until about 3-4 weeks into flowering, and problems seem to be more intense on some plants vs others, even though they all get the same feeding water.
I've harvested several plants already, and my yields are definitely low, but the bud is still good. Since I've harvested, I've been able to check out the root systems, and they seemed kind of week but I don't know exactly what to look for since I've historically grown hydro. Everything is climate controlled, and I'm using C02.
Tapwater - I'm told Denver's tapwater is fairly hard but I have no way of really knowing the mineral levels. Using pH drops, test between 7.5 and 8.
Feeding Water - Added to tapwater, 3tsp/gal GH florabloom, 2tsp/gal GH floramicro, 1tsp/gal GH floragro, 1tsp/gal botanicare vitamino, 1tsp/gal rock supercharge, 1tsp/gal rock resinator, 1tsp/gal GH cal-mag
Feeding Water pH - 6-6.5
Watering - Feed until water flows from bottom, runoff is collected below raised platform
Runoff pH - 6
Feeding Frequency - Once a week, tapwater in between if necessary
Substrate - Sunshine Growing Mix #4, 2 gallon pots
Light - 400W HPS, ~1.75 feet from top of canopy
Day C02 - 1400-1700ppm
Day Temp - 80-84
Night Temp - 76-80
Relative Humidity - 55%
Observations: In between fertilizations when flushing with plain tapwater, symptoms progress more quickly. Immediately after fertilization, symptoms progress more quickly. It's almost like no matter what I feed with, it makes things worse. I've checked for mites, definitely aren't any bugs. It's so confusing because it's like if I cut all feeding nothing really improves, but if I feed normally things get worse. I also was adjusting my pH before I started adding cal-mag to more of a 6.5-7, versus what it is naturally after nutes more of a 6-6.5, and this actually seemed to have the worst effect. Adding the cal-mag and not adjusting my pH has slowed the symptoms, but still has clearly not fixed the problem. Lately it seems like the leaves have stopped browning, and started yellowing.
Picture 1 - Most recent, brown spots stop progressing, leaves are becoming more yellow though.
Picture 2 - Brown spots
Picture 3 - Middle tier leaves seem affected more than bottom and top. Small, inner leaves are virtually unaffected.
Let me know if you have any questions guys, I really really appreciate your help!
