How do I get my plant to stop blackening

That’s almost certainly coco. It’s damn near impossible to overwater in normal circumstances. It’s hungry and I’d guess you haven’t fed it anything yet. That’s my 2 cents.. assuming it’s coco. Not fed at all or coulda been overfed if you have been feeding

The diary is lacking information and it does not look like the medium is to moist. It does look like it is just peat with no extra perlite or anything. The leafs are a bit warped and that could indicate to much water but I am leaning towards they got to much feed as they are also crispy and over watering does not make leaves burn and get crispy. Also note the medium does not look to wet and peat on its own drains well enough and almost becomes hydrophobic at times. I would look into getting more detailed information into your diary so we can assist you better. I would also look into getting a TDS pen to monitor your feeding concentrations in the solutions your giving them. Your diary say your growing 5 seeds all gelato #25, are all 5 seeds doing the same thing??? Take a qucj read though this article on the levels of EC/PPM to aim for as well as PH. I will open some doors for you and give insight on the subject, growdiaries.com/journal/best-ph-ec-and-ppm-for-hydroponic-marijuana Happy Growing! ***disclaimer, multiple people are answering all questions as there is a contest called GOTM, when a user is selected as the answer they get a point. Please see the contest page for information regarding the details: growdiaries.com/giveaways/GotM-August-2022 Please note, when you reply to anything on the questions part of Growdiaries website, no one will be notified of this. Not even if you use a "@" tag in their name. Best to reach out to them in DM using your inbox, it can be found in the bottom right hand corner of the site. It's the small paper airplane button, it will be highlighted green if you have new messages***

You have absolutely no information about this grow in your diary! This looks to be a case of over-fertilization but honestly, you'll need to fill in more information about this grow - otherwise, all you're going to get here in terms of advice will be just plain guesses... and those guesses might be wrong and make even more problems for you. You can edit your diary and fill in more relevant information... so please do that so we can actually know what's been going on and can give you GOOD advice...

High, You give her too much water! A young girl like this maby drinks 50ml a day. This is coco when I see it right? Then you can give 100 ml a day for another week. When her roots become bigger and she becomes more thirsty you can give water till runoff. Happy Growing! 😋