I have stunted yellowing brassica seedlings. They are in 2" square modules of West Riding potting compost. I used to use their seed and module compost but it didn't have enough go in it to take brassica seedlings to the bulky 4 leaf stage. Can compost be too strong? I am reluctant to go out and buy different compost because I have - I know - 96 eighty litre bags of this stuff. Lettuce and salad crops, sweet corn and all the toms and squashes are doing fine - brassicas - awful.