Plant has top leaves curling up

PK def bs of Mg overdose also N def

well for one it sounds like your watering habits are bad. you don't just give pre-ordained volumes of water that make you feel good. You use as much as it takes to properly accomplish the task. if you are treating it like a soil, then water it like a soil... fully saturate then wait for top 1" to dry. HP has okay drainaige properties but you want to add some vermiculite or perlite or similar to make it more optimal. You want about 50% of teh volume to be one of those amendments and HP comes in at 15-25%, if i recall. yeah, it's called "high porosity" but reality is what matters not some label, and it needs more. if you ever swtich from gaia green, i assume the top-dress?, treat it like a soilless medium, which is what HP is. Similar to above, but it is important to get 10% runoff or more, religiously. This is what maintains a consistent equilibrium of nute concentration every single fertigation -- impossible to build up in soil.. still possible to over-feed, of course. Eliminating one of those probabilities makes diagnosing so much easier. If you are systematic about adjusting formula based on what the plants say, you really shouldn't need to do much different from one grow to the next... Constantly making drastic adjustments is a sign of a poorly balanced feeding regimen. A light at 50% and 24" away is highly unlikely to be the cause. If sized properly for your tent, you'll probably want about 65% with 18h operation and 100% with 12 hour operation. If the tent is a bit smaller than the light is made for, reduce those numbers further.. it's proportional to area and hours of use (inversely so for hours, of course). While they often lie about umol/s, PAR, PPFD, umol/J, et al, they are usually pretty accurate about estimating area of coverage in "flower", which would be 12 hour/day operation. anyway based on your description of how you add water, i bet at this point in the grow some sort of rootzone related problem has developed. If you had the light super close and signficantly higher than the context i gave above, that is also potentially related, but otherwise can be ruled out. Since the other plants how no problems, i highly doubt it is light related. So, don't be afraid to put it back where it was before if the growth pattern was fine. If you reduce light too much you'll induce excess stretching. i'm assuming there was time between "I just watered with recharge and gave them a gallon each" ?? if you dumped a gallon on of 1 thing, then immediately added another you end up washing the first batch out the bottom. in any 1 watering, everything should be mixed together. If a couple products cannot be mixed, then you need to plan accordingly to work it in on a different irrigation without the product it doesn't jive with. dumping 1 galllon, then another is not the right way to do it. again, you use a volume that accomplish the task of fully saturating the pot - in soil a minimal amount of runoff is fine to ensure this, but you don't want a lot of runoff leaching off your amendments and fertilizer you paid for. Treating it like a soil as you are is a completely different animal in this regard (runoff). soil fertilizers take a long time to provide... there's a dissolved mass that feeds the microbes, which break it down to the point at which those nutrients can enter the plant. there's a lag between adding ferts and when it becaomes useable by the plant and that is above and beyond and 'slow-release' effect gaia green might have or anything else like it.