Even though the grower below me is a cheater he is correct this time. That's way too much water when they are this tall you only water around the base of the plant not the whole medium and then wait for it to dry out before watering again that way they will grow normally it will still grow its just going to take a while to recover I would try up the humidty if you can that might speed it up abit when dried out. Perlite is designed to hold onto water for a very long time so watering alot is only going to attract nasties and drown your plant :) Try upping the temp abit too that can help dry the soil out quicker :) Best of luck anyway im sure you will do really well :)