I just watering every 3 day, i have 1000L recipient i hold the water, i check ph and ec , with the pump in 20 mins its done, i wait 20 mins and with the pump put back water and after i just complete with water and fix ec and ph.very easy and comfortable. If you want to try it i recommend to follow limbo holland ( search on youtube) , please do it everything same like him dont improve or try something else cause you make it wrong.I bought a 1000 tank instead to make the tank under plants and now its occuping space and its more hard to move the pump meters away or on another room, just said dont improve another stuffs , the single problem why i preffered to not make the tank under plants because of height i was afraid to not grow to high the plants to burn the lights the plants. I made 4.1 kg with 4 dimlux 1000w on 3m x3m room( northern lights and critical from seeds half/half (80 plants)
I would guess your flooding takes too long and then they sittin fully flooded for 20 mins then you drain ? I think that’s the problems
The extra flooding has waterlogged the Mapito , so roots not growin , so upper plant mass not growin , so ec not being used up , one thing leading to another
Prolonged flooding is causing waterlogging and then ec build up , curled leafs and too much n in leafs dark green
Why don’t you just say they are over watered?? 
I’m interested in Mapito. I wonder how well it would work in autopots 
Thanks. Now when they are small probably you right! But when are bigger its normally , you can check limbo videos he doing the sane. But now i just checked in lower corner of the room when its the lowest point when i drain the water out , and i have 6.2 ph and 1.06 ec. The ph its to high , but i saw also the plant and Branches have purple colour in few places.
Check limbo holland videos on youtube. Very nice guy
I’ll take a look. Thanks 
@Esrgood4u , I just use a garland tray 12cm deep and crates from band q , they used to be a fiver but now 7.50, 15L grey , very nice crate rubust nice quality
I’m thinking this Mapito is sort of a wick system
You flood for a while then allow the medium to dry out. It won’t work with autopots then. It’s a flood and drain type of medium.