Sup crew I need help. I’m new to growing (2yrs) and I seem to have a hard time with both autos and photos both yellowing on me week 4ish of flower. I’m on well water but only use RO water for the girls. The pH is good, running hlg lights so good there, always used canna coco the basic mix (handful or two of casings, perlite, and coco). Sometimes I add a handful of sand, and insect frass. But never have any bug issues anymore. I’m using spring pots from auto pots fabric #5. And I made some custom screen pots too. Before I got my hands on the grow dots I was using the canna aqua line and of course Recharge. And will grow decent bud but by week 4ish the leaves always look like this. Now that I’m week 5 of flower with Grow Dots, the same thing is happening. I think I’m totally missing something. The reservoir is 12 gallons but I only put like eight at a time just RO water. These plants are sour diesel from fast buds both planted 9-1. The one on the right is 2 tablespoons, one on the left 4 tablespoons. Thanks for all the help.
Something is up with your media’s pH buffer I suspect. The brown spotting on the leaf veins are a symptom of manganese not being available. It’s only needed in trace amounts and could be locked out due to pH being too acidic. It’s common for coco to go acidic with hydro nutes from salt build up half-way through flower. It’s a good idea to do a simple rinse about every 4 weeks. Week 5 is where the coco pH can swing. Check the run off pH and ppm by pouring an equal amount of RO to media as quick test to see range.
Jmystro…. a PH Swing, a Temperature swing, and a NPK toxicity all walk into a bar and order a tall glass of Calcium-Magnisum. LOL.
HEY Duurl, I’m sure Real Growers Grow dots have plenty of the NPK Nitrogen Phosphorus Potassium to keep you plant growing as those are the main components for Macro Nutrients. However, what a plants uses more frequently and is more readily available is calcium and magnesium.
I like to think about it like this, nitrogen is for keeping it green, Phosphorus is for new growth, and potassium is transportation.
You can grow a plant for awhile without Calcium or Magnesium, especially autos, the plants just making twigs and bushy leaves. But the second the plant starts getting exercised with stress or growing different there is no back up reserves of the micro minerals Calcium and the other trace minerals Cal-Mag offer. You can over due it on Cal Mag so watch out, but growing in coco I have found the plants took more cal Mag than NPK. It may also be my Advanced nutrients bottle as well though
I suspect the issue here is from using RO water with coco. There is no pH buffer with RO and the media has probably gone acidic. Calcium and magnesium are not used in the same or higher ratio as nitrogen, phosphorus and potassium, so no plant uses more calcium than n, p or k.. Calcium and magnesium are not the issue here either. Manganese, not magnesium is the trace element that’s showing lacking causing the brown spots in the leaf veins. The Grow Dots have all the essential elements plants require when mixed in proper amount and given time to break down as it’s slow release.