Feed every time with coco so as not to rob the cation. If you want to "flush" as many call it, simply charge the water with a bit of calmag to satisfy the cation and run 2 or 3 times the volume of the container. Purging your medium keeps the salts from building up, and also puts the plant into overdrive for the next feeding. In the end you're really just simulating mother nature, and she's done a pretty fine job to this point. Don't see the point in using molasses instead of CalMg, since it's ratios for Ca and Mg are in the wrong proportions. Calcium is the most used macro during flowering and can be provided in other ways than dumping a bunch of sugar on your plants. For fucks sake i hope it isn't added for "flavor" too.... yikes.
You're worried about wasted nutes yet you want to crank up the ppm in a coco grow? Your still dumping a bunch of money out the bottom of the pot, wether you run a ~.7 EC and water frequently, or roast the shit out of them with a double dose and wonder why even in coco you end up with nutrient antagonism. Feed a lower ppm but water more often. The great thing about coco is you can slow the pace of growth by doing the whole lift test, or you can water twice a day, introducing more oxygen to the roots (that's a good thing) and watch them go crazy. I look at coco as if it's more of a hydro system than soil.... watering is a damn good thing, and you cant overdo it so long as there is proper drainage. Someone in this thread had mentioned a balance of nutrients being a product of running plenty of food through those coco pots..... DING DING DING!!!!!! IT's really that simple.... a balanced diet keeps everything available to the plant. Just make sure you have plenty of N to build the foliage, and don't skimp on the Ca and Su during flowering. Good roots = lots of foliage = tons of flowers. You can complicate things as much as you want, but will likely end up in the sick plants section with the other "gotta have the fancy label even though i haven't learned the basics" chumps.
Great thread!!! I too will be growing for the first time in coco I went with Gold Label 60/40 puffed lava rock anybody have any luck with this? Like the last grow in FF soil i will be using the same nutes all but switching up grow big with the hydro version keep up the great info!!!