Hi everyone, Using 60 coco 40 perlite mix. I have 3 ww in a 4x4, temps 81 to 68, 55-65 rh. 400 COB. This is 7th week of veg. I made every mistake along tbe way... Using GH Flora series and added calmag @ 3ml/g on feeding days. Ive been watering with aerated (24 hrs) tap water that is at 200 ppm. Just got an RO system today, now i just need to find the time to install it.. Anyways, thought this might be related to the issue. First 5 weeks I used distilled water and used tsp calmag/gal. I need some ideas on what may be causing the symptoms Im seeing on the two weaker plants. It looks like two different issues, but you guys tell me.. Please take a look at the pics and let me know what you think and thanks in advance for help and suggestions. Note: Reposted from Absolute Beginners as this is forum seemed more relevant..
You should be feeding daily in coco/perlite. You don't need to rotate in days of just water. Distilled is never a good thing. It will be so thirsty for minerals you'll need to put a bunch of calmag in it and you'll still be lacking some trace elements. Your tap at 200 is probably ideal. That's what the nutrients are designed for. They look like they're experiencing potassium deficiency to me. Coco is better with more often watering. Sometimes up to twice a day when they get larger. It doesn't like to dry out as much as other mediums. ph should be in the 6.0 range.
Hi Tbone, Thanks for your reply. I hadnt considered a potassium def until you mentioned it.. Did a little research, but I'm still thinking maybe mag def due to theor horrific history. The stems are deep purple on the worst two...I started these with distilled bottled water and only started using tap a few weeks ago. i think when i switched to tap, they got Calcium but not enough mag... I also grossly underwatered and underfed for the first month, its a miracle they survived.. I treated it like soil, even though I read 100 times not to.. Looking at my runoff data, I still think Im underfeeding, but I aas afraid to overwhelm them and cause burn. Considering switching to Coco specif8c nutrients and maybe keeping the tap water... Would you switch nute brand in the middle of a grow like this?? If so, suggestions on brand.
I grow DWC and promix/perlite. Potassium deficiency can mimic magnesium def because both can cause the yellow stripes between leaf veins. The K def. version starts more at the tips and has brown/yellow tips like you get with nutrient burn. Potassium Deficiency | Grow Weed Easy I also see some phosphorus deficiency. Your brown blotchy areas. I think it's missing a little P&K in it's routine and possibly off in ph causing reduced uptake. It looks like there's plenty of N.
I previously read through the GWE page you referenced, but im new to gardening and havent developed knowledge or an eye for distinguishing these things, so thanks for providing your experienced opinion. I use this as my starting point... Ph has been within range (5.6-5.9) almost the entire grow, the problem, I think, was due to underfeeding. In trying desperately to avoid overwatering and burn (the two beginner mistakes I kept coming across in my initial research), I caused defs and stunted growth instead. Read up on Ironhead's method and thinking of switching to that since the GH starter box has a few of the items needed vs having to start from zero with coco specific base nutrients. That would also eliminate the need for RO. Hope that takes care of the deficiencies. Thanks again cor your help Tbone.
If you keep up with Ironhead's stuff he recently switched to the lucas formula feeding which is what I use. It seems to be very successful for me and many others. It really helps simplify the NPK numbers and profile. It give you much more control of the NPK numbers easier. I'm not a coco grower but from what I've heard it's very difficult to overwater in coco. In fact coco seems to need more often watering then other mediums. You want to keep it at an even amount of moisture instead of letting it dry out between waterings like you would with other mediums. The theory is that coco is capable of holding a bunch of oxygen and aerating at the same time as feeding. That's one reason it makes a great hydro medium. It just takes a slightly different approach then say promix or perlite. The lucas formula is just GH flora micro and flora bloom. You don't use grow. You always feed twice as much bloom as micro. If you feed 4ml/gallon of micro feed 8ml/gallon of bloom and so on. You can add calimagic to this routine for coco since it does consume more cal/mag then other mediums by it's nature. I've also seen posts recently about led grow lights consuming more cal/mag then other forms of lighting. When using lucas with coco and tap water it's possible that you won't need calcium Micro is already 5% calcium and if you have some in your tap it's going to probably be enough. Many tap water lucas/coco growers simply add epsom salt and that is enough additional magnesium with the calcium in micro to keep the plants satisfied. Epsom also supplies additional sulfer which is a very little understood but necessary nutrient. The plant uses about as much sulfer in the grow cycle as magnesium but nobody supplements sulfer unless you use epsom. The gh micro is your nitrogen component. It's 5-0-1. The bloom is your p&K it's 0-5-4. If you follow the formula you end up with about 5-10-10 for your npk ratio. Cannabis is a phosphorus and potassium hog even in veg. This formula stays the same for veg and flower although as the plant's size increases you increase the strength of the mixture. I also add other supplements. In flower I sub in GH liquid koolbloom. When using that instead of standard bloom you add equal amounts compared to micro. Liquid koolbloom is 0-10-10. You always have the option to increase/decrease nitrogen by itself when you look at a plant and decide it needs more or less. You of course can also limit p&k by itself if you think the plant needs more or less. I like the control this method give you as a hydro grower. The other ways of using the lucas formula are single bottle options. GH floranova bloom and GH dry maxibloom. Either one is roughly the lucas formula and many growers have used maxibloom alone in particular mixed with some epsom salt or cal/mag to have very successful and cheap grows. Maxibloom is quite cheap in bulk and it's really all you need for npk. When you buy liquid nutrients you pay for water in some respects. Dry goes further. I think you just have multiple deficiencies that will all sort of settle down if you just feed daily. If you have the option leaning your NPK ratio more towards P&K like the lucas formula may give you more success. If you never feed more then 50% recommended strength you'll never burn a plant.