hello matt, thanks for your reply, it is good to talk, discuss and debate, that is how we learn.
in the old days, i used to also grow some naughty stuff and had great success out of the water as well as in with the daylight tubes. a couple of years ago i had another go in a small way but this time i bought a reasonable size led light that was more expensive than what most normal every day fish keepers would pay for their led tank lights, and the results were a bit disappointing, slower growth and weaker smaller fruit. this perplexed me a bit so i researched a bit and it seemed to boil down to cost. i needed a much more powerful and expensive led light, more than i could afford. i think it is all about penetration. (my tank is 24 inches high, a bit of a pain because being only a short ass, i my shoulders get wet doing anything on the bottom of the tank) maybe the leds that can be submerged might help out with that. when i had my at-home tanks, (not the 20 fry-raising tanks) i was lucky that here in plymouth (liskeard now) there was a warehouse that sold old and disused commercial stuff and i bought old floro units with the tubes in. i replaced the tubes with daylight ones.
i have always looked upon algae as a bonus i suppose because i have always had algae eaters of some sort and a good supply of single-sided razor blades. (needed for when i cut laminated glass) now with over 200 shrimp in the tank, a plec, 2 otos and about a dozen assassins, algae is a real bonus because i often don't feed anything for a few days and it is great to see loads of shrimp munching on algae all over the glass.
i used to make nice deep hoods out of ply to house the floro units and i stained the hoods with linseed oil, brings out all of the grain.
anyway, like everything else tank lighting is a matter of choice but for someone with plant growing probs it is well worth trying daylight tubes.
word of warning, if you use linseed oil wash your hands before going to the pub because it makes beer go flat
that was one of the first things they used to teach you when becoming a glazier.