do you add any supplements to the tank at all, swords are pretty fast growers, but dont last that long without any type of special additives In My Experience. the lighting sounds good to me though, as they are very picky about lighting needs. they do fine in low light. what is the stock and how large is the tank, as a tank with no fish, tons of plants and no added supplements is not going to go very well, as there arent going to be a substantial amount of nutrients for the plants. maybe there could also be whats called an imbalance, when there is high light but no added ferts and Co2?