Hey folks, been growing in dirt for a yr now and decided to try DWC this time. I am having a small prob with the plants and want to take care of it before it gets too much worse. First off I have 3 strains going, the largest is a clone froma friend and I believe the strain is purple kush, then I have a fem strawberry cough and a fem white widow. Ph is stable at 5.7-5.9 temps are in the mid to upper 70's and I have been using the Lucas Formula. PPM had been at 850 when I saw the problem start. I thought I may have been starting a salts build up so I ran ph'd water only for 24+ hrs and the ppm rose by about 50 points only so I refilled the buckets with solution at 650 ppm to see if that helped eliminate the yellowing. The new solution has been in for 48 hrs and I still am seeing some new yellowing. Anybody with hydro and dwc in particular please send suggestions and help so I can get it on track quickly. Pics 1&2 are the PK, #3 isWW and 4 is the SC
Looks to me like your nutes are just a little bit too strong. Shoot for 600-700 ppm. Then let them sit for a few day. Its usually takes a couple days for your plants to react to your nutrients. But defintetly looks like nute burn to me. Here's the guidlines that I use when it come to PPM in hydro. Seedling/Rooted Clone: 300-500 ppm First week or two of Veg: 600-700 ppm Last couple weeks of Veg: 800-900 ppm Beginning Flowering: 1000-1200 ppm Late flowering: 1300+ I usually try to max my plants out. Meaning, I increase the nutes as strong as I can get them, so I just get a little tiny bit of tip burn on the ends of the leaves. This tells me there getting all they need. Then I back off, just a little and let them go. And try to stay in between 5.5 and 6.0 PH Check this out... these are the ranges in Hydroponics that each nutrient gets locked out at. You stay out of these ranges and within the above ppm ranges and you'll be good. This is only for Hydro... Nute Lock Out PH Ranges Nitrogen (N) 4.5-5.0 Phosphorus (P) 6.0-8.5 Potassium (K) 4.0-4.5, 6.0-6.5 Magnesium (Mg) 2.0-5.7 Calcium (Ca) 2.0- 5.3 Zinc (Zn) 5.7-8.5 Iron (Fe) 2.0-3.5 Sulfur (S) 2.0-5.5 Manganese (Mn) 2.0-4.5 Boron (B) 2.0-5.0 Copper (Cu) 6.5-9.0 Molybdenum (Mo) 2.0-5.5 Nickel (Ni) ???
And another thing. I just noticed that you were doing that Lucas Formula. I wouldnt mess around with these formulas that people come up with. No offense to whoever Lucas is, but these nutrient companies do tons of research to get there products to work right. Changing that up just because some one see the 3 main nute numbers in the front of the bottle not adding up right, isnt a good idea. Taking one nutrient out and substituting more of another isnt going to help. Each of that 3 part system has its own chemicals in each. If you take one out and increase the other, you may be adding too much of something leading to nutrient lockout or nute burn. I'd keep it simple and just do what the back of the bottles suggest. It definitely looks like nute burn to me, but if your only at 650 and still seeing yellowing, then you have lockout. Drop the nutes down a little more and see what happen. Give it 3-4 days to show improvements. Also, how are you measuring the PPM? Are you using tap water or RO water?
Thanks for the quick reply.. I have read everything you suggested 3 times or more prior to starting this thread. I agree that it looks like burn . I replaced my original solution (which I had at 850) with plain water (tap) for 24 hrs and the ppm only went up about 50 points so salts lockout seemed not to be the case. When I redid it again I set the ppm at 650, that was 48 hrs ago. As for the lucas formula, a lot of folks on here and other forums swear by it so I thought I would give it a go. If the prob continues thru the weekend I will flush with water for 3 days and then go to the 3 part and see what happens. I also just started a grow journal in the indoor section. Figgered if I was gonna fuck it up I wanted witnesses, must be the voyeur in me..........
blakeshouse, what's the EC or TDS reading of your tap water only? Lucas is meant for tap water that is less than 100 ppm. What kind of lights are you using? Lucas has different formulas for CFL and HID. You probably know that already but just checking, can't hurt to check. I have to agree with you that Lucas seems to have a credible formula. I have read tons about it and no one I mean NO ONE has said anything negative about it. I'm thinking that if you are running HIDs and you are using Lucas' old formula you might be running 0-5-10 when you should be running 0-8-16, the lower than required formula might be leading you to early stages of a Mg def.