Whoops! Just noticed one plant was growing much quicker than the other and thought "Mmmm, that's odd". But on closer inspection it would appear I forgot to plug in the submersible airpump on the lagging plant after I changed the nutes on 22nd (5 days ago!) . Strangely the lagging plant flowers appear to be more developed (more pistils etc.), even though they are identical clones. I wonder if the lack of air pump has anything to do with it?

I think I will change the nutes on both plants tonight (wasn't gonna change them until Thursday), just to be on the safe side.

I'll post a pic or three later, after changing the nutes....