I took pictures to LFS (in the UK) and they said iron deficiency... is this right?
4x T5 55w on 8 hours per day
CO2 on 2 hours before lighting and off 2 hours before lights
Good flow with four powerheads
2 x canister filters (aquamanta EFX 400's)
UV 2 x TMC 400
100 fish (tetras, guppies, Siamese algae eaters, petricola synodontis, plecs, krebs, harlequins, amanos etc
Ferts EI from the Nutrient Company, dose as per intructions
Water change > 50% weekly.