yep veg is generally the easy part flower is the business end of proceedings when the plant switches modes & really starts to take on nutrients
if something ain't right , flowering mode is where you'll see that issue come to the forefront
pot size = bigger the better imo but 10gal during winter should be fine , during summer double that would be better even if you have multiple plants
in a 20gal with a bit of training to spread them out a bit but in general the larger the soil volume the more consistent the moisture will stay , it won't
fluctuate as quick , one of the things life in a pot won't hang round for is drying soil & if you loose these organic matter composters you loose the food
source for the plant , what comes out a worms arse for instance are nutrients in plant available form (in the right ratio like cal to mag) otherwise organic
matter uncomposted is useless as food for a plant
mam p is a liquid culture of bacteria , chems will kill them , chlorine , fluoride , PH up /down will all cause problems for those bacteria , considering the price
of mam p last time i looked you want to get the most out of it so killing them means your dollars are wasted
in a living soil system you have no need to PH liquids , this is hydro mentality , a living soil system will sort PH out for you , i never PH anything when watering
i always water slowly = small amounts , letting the the water slowly seep down & wick through the pot , a bit like rain would
you do use things like dolomite or crab shells = calcium carbonate ( many options ) as liming agents in soil mixes but once the life in the soil is thriving you
have no need to PH adjust any liquids
keep a lid on your rez as I'm sure you already do for hydro & agitate as your doing
yes using your arm to stir water will help remove chlorine & fluoride but would rather find a better way than using your skin as a chem remover
mulch layers can also work as a filtration system as long as you water slowly as mentioned above
I use EM-1 which is not exactly the same but a bit like mam p & it's PH is 3.5 roughly & i never adjust PH , as long as the life is active in your soil they will
sort PH out for you
read the first post on this thread
https://forum.grasscity.com/threads/no-till-gardening-revisited.1400505/ it'll sum up what you want to achieve in a living soil system
read this as well
https://buildasoil.com/pages/the-complete-system for the same reason as above