PLEASE HELP!!! CalMag deficency?

Aquí tienes un enlace dónde te explica todo a la perfección, espero solucionar tu problema. https://www.cannabiscafe.net/foros/forum/cultivo-de-cannabis/cultivo-en-interior/190201-control-del-phsustrato-ph-del-agua-ec-del-sustrato-ec-agua-60-%C3%83%C2%A9xito-en-el-cultvo

Not cal/mag, but burning from feeding too much or too often, or both. Autos usually get by just fine on half strength nutrients. In soil it is a schedule of plain water/plain water/feed/plain water/plain water/feed, so that your plants are only being fed every 10-14 days, this is because soil "holds onto" nutrients more so than other methods and your plant needs to use up what is in the soil first, before any new nutrients are added, otherwise burning occurs. No need to drown/flush your plants, this can release even more nutrient salts from the soil and worsen the burning. Just give plain water for the next 10 days, in normal amounts and at normal intervals, before resuming feeding with half strength to what you have been giving so far and your plant should recover and continue growing. The damaged leaves will not recover, but all the new growth should be ok. Hope this helps, Organoman.

You've got a number of issues here but they all boil down to an overload of nutrients..... What you need to do immediately is to flush with ph'd water (3x the size of the pot so if they're in a 3 gallon pot, you want to flush with 9 gallons of ph'd water). Then let her dry out. When you start your nutes again, at their age, I would knock back to 1/4 strength grow nutes (I'm not familiar with your nutrients but you want to reduce the nitrogen levels as you go into flower) and feed only 1/2 strength bloom nutes the first time you give nutes. If they tolerate that, you can up the bloom nutes the next week but keep the grow nutes at 1/4 strength and cut them out completely by week 6. You don't have a calcium problem and you don't have a magnesium problem so CalMag is not going to do anything for you... Autoflowers can generally go the first 2-3 weeks of their life without any added nutes at all... I didn't quite believe that with my first grow (Big Bud) and thought I was doing them "a favor" by treating them to such a delicious banquet of nutes.... I couldn't have been more wrong. Still, the good news is that they're AUTOflowers and are just programmed to give you a harvest whether you treat them horribly or treat them royally... it might not be the best harvest you could have gotten - but it will be a damn fine one! Of that, you can be sure. Three rules: #1 - always ph your water/feed and then check the runoff ph to make sure IT is in a decent range (6.2-6.5) #2 - don't feed autoflower too early, start them off at 1/4 strength and don't overwater #3 - don't worry... The good news is it's an autoflower and she'll be just fine.