Depends on how hard you water is mine comes out of the tap at over 400ppm so i struggle to get enough Fe in the plants so I have to use Fe EDDHA which makes the water pink , I have also got Fe DTPA but it is broken down fast in light, with soft water you get away with just using Fe EDTA, so it depends how hard your water is and what the resting pH is of the water. My DC is nearly yellow yet the pH of the tank mid photo period is 6.9pH. It was fine at first but then the AS buffering capacity ran out and my pH increased next FE deficiency started to show in plants hence I started to use another Fe chalate.
Came home from 2 weeks hol yesterday one tank (500l) was 690ppm and the other 50l was 800ppm
spent about six hours doing two tanks and still have filters to clean tomorrow and a bit of tidying up ...... 2- 3 hours easy
Also from reading around chatting with other members and experts hard water has lots of ions and complex reactions can/do take place which can leave you plants deficient even though you have dosed enough ferts. Most scapers esp professional use soft water or a mix of RO and tap water as it makes it easier to grow plants. going for a big tank ? then if going down the RO route more cost plus will need a holding tank/tub
Hard water also over time reduces the cation exchange capacity (CEC) of aquasoil, as the excess ions block the active sites as the water isnt soft enough for the H+ ions to displace the other ions bonding with the AS so basically your active AS becomes inert over time
so your fert regime will need to be spot on when this happens of cousre you can always dose the EI in more excess but then that increases the hardness again and more ions in the tank and ppm keeps climbing.
Having a 3 sided tank close to the wall also has an issue unless your Ambidextrous (I m not ) so when using left hand close to wall and using pinsettes reaching down in 50cm of water then another 3cm if hood is off ( 10cm if hood is fitted) is a little tricky, plus you cant bend down and reach the bottom off the tank with the pinsettes at the same time !!!!! plus bracing gets in the way if hooded all the time
3 sided tank you have all the plumbing going up one side - tricky !!! so plumbing can end up complex and takes longer to clean - day job easy for me.
Not trying to put you off, as what one man can do so can any other man, but an open top tank not too high say 40- 45cm then it needs to be wide at least 60cm and your time need to do maintenance is well cut down, before I got my Maxspect gyres it use to take 10-15 mins just to take the hood off
PITA
I get away with a hooded tank as its open top hooded - only had the lid on once after spending many hours custom fitting my four kessil 160 tuna suns to it, if you going high tech think hard about having a hooded tank. I spend many an hour with my hands in my tank and I do enjoy it most off the time but I couldn't leave it for weeks.
Choosing the right plants can help cut down the mainitance and not having a carpet will help too.
Open top tanks have lots of lily pipes you could use straight off the shelf