Well normal seasol has not got any nutes in it that i am aware of so must be the powerfeed. I have given my little baby seedling foliar feeds with Chilli Focus and they were fine, haven't tried Power Feed misting though, may try that today.
I thought the seaweed stuff didn't have any nutes simply because it didn't have an NPK listing on it, but I read somewhere else that it does have some.
edit: from the seasol site faq
What is the NPK of Seasol?
Seasol contains only very minor quantities of Nitrogen, Phosphorous and Potassium (N 0.10% : P 0.05% : K 2%). Seasol stimulates growth because it contains naturally occurring growth stimulants that have profound effects on plant metabolism. The growth stimulants in Seasol produce strong healthy growth of leaves, stems and root systems, and result in enhanced flowering and fruiting. They also strengthen plant cell walls, thereby increasing resistance to stresses such as drought, heat and frost, as well as insect attack and disease. Seasol also contains many trace elements which are essential for plant health.