I’m on the lesser flow team 😉
(90cm x 45cm x 55cm tank, 2 Kessil A160, Tropica diffuser, Eheim Pro 4 350 (1050l/h), intermittent Eheim skim, lean dose fertilization... minimal algae tank)
Unless you’re planning riverine fish, many tropical fish are from low flow areas and will struggle in high flow systems
Seriously Fish species profiles include natural habitat information so easy enough to select fish more suited to a high flow tank
For plants, we try to prevent any “dead” zones but these offer respite to fish
Tank looks grand 🙂
Not sure about double dosing the liquid carbon, some plants are sensitive
Daily 25% water change may do more re increased CO2
S repens may lose all leaves, just wait for root growth & new life - read Tropica’s article
Remove any damaged/deteriorating leaves