Well its not highly recommended to flush coco with plain water leaving them no feed, and I`d only do it as a one off if I`d fucked up in the first place, which I`m thinking I may have done. I don`t as you suggested ever feed with anywhere near full strength nutes, if you do I`m not surprised you have to keep flushing mate. ;-)
Rather than feeding heavy, light, plain, you` be much better advised to get the feed strength adjusted to the plant`s liking in the first place. I`m not saying an occasional flush is harmful in coco, I dont believe it is, but I dont think its a good idea to have it as a regular routine, and I`d definitely prefer to leave them a little food afterwards. Thanks for your advice `n all, but my problem isn`t going in with full strength nutes.
I`m suspecting that it may be, as Scroger suggested,that the Calmax strength was too much and caused a problem with the delicate balance of Cal and Mg in the medium causing the plants some difficulty absorbing the Mg through the roots. I upped the strength of Calmax from ec0.3 to 0.4 when I saw the problems starting with the Big Bud, trying to compensate in order to give more Mg. I think maybe ec0.3 Calmax was a bit strong in the first place and starting to lock Mg out. I`m thinking the Big Bud pheno was most susceptible and showed signs first. When I upped the Calmax I think I may have provoked the problem further and the BB got worse and the Armageddon then Grapefruit started to struggle too. Since Scroger mentioned the Calmax stength, I reduced the Calmax to ec0.2 and started feeding enough for a good flushing run off on a daily basis and gave the plants a good foliar feed of Epsom salts.
I`m not sure about this, but they certainly look a little better in both colour and vigour just 30hrs after their foliar feed. but the Big Bud still look poor but they were by far the worst affected so that wouldn`t be surprising. I`ll keep a close eye on them and keep you all up to date.
I hope this is the problem as its gonna be so easily remedied if that`s the case, its far more likely a scenario than some plastics off gassing, thinking about it I think that would show different symptoms to the Mg def look, it sure did in the grow tent.
I`m wondering now if it might be worth mixing my RO water with tap water to bring my base water to ec0.2, it`d save money on Calmax for one thing, and would overcome the problem of too much Nitrogen especially during heavy flowering. It feels like sense to me to give this a go to maybe just one tray of plants and see how they like it.
I`ll take some pics tmro and post em up. I`ve been looking in on the tent grows, they`re looking impressive. The buds on the flowering plants are growing and swelling well and I think they`re somewhere like 5 weeks into flower now. The 4 plants in veg are looking good too. I took some pics of both tent grows and will post them tmro too, as I cant find the cable that hooks up the camera to the computer! Its some good bud porn though fo sho!
As I said, I`m not certain this is my problem, but I`m feeling a bit better about the prospects of this grow now, and to my albeit limited knowledge of the unique way that coco uses and stores elements, it does fit I think. Let me know what ya think guys??
Cheers for now, Toke
heres a pic of the leafs off my white rhino 
