Hi all, complete newbie here. Decided to take a bash at this going into lockdown and thought it was going quite well until the yellowing (leaf and veins) and brown spots have started oppearing. I have researched this so many times but cannot determine if this is a Nitrogen/calcium/Potassium deficiencies etc. or I am overthinking this. I have linked a few pics of both of my plants and an example of a leaf that I took off.
Admittedly, I have not got any fancy nutes or anything and have been using tomorite once a week (3ml per 1l of water).
Many thanks for reading and any advice you may have.