Hiya Harry, I've been doing some looking about for you and with my experience in plant problems (trust me I've had a few)
I would say that there's a few things happening here but I am no expert.
Firstly I think they are slightly overwatered which will give you leaf curl and a general shabby appearance, secondly there maybe a touch of nitrogen toxicity, if you look at the colour of the leaves they are a dark vivid green and the lower affected ones are clawing badly and dying.
Maybe you have a touch of heat stress from the bulb being too close too that would cause clawing and browning of the leaves closest to the light.
I think your ph may be a bit out too and this will make any underlying problems worse.
I would give it 5 litres of ph'd water to 6.5 then slowly flush it through your pot this will wash out any nutrient build up in the soil.
Secondly let the soil dry to where you think it needs watering...then leave it for another day, mix up a 1/3 to 1/2 strength feed for the first feed after flushing as I see you do have nute burn on the tips of nearly all the leaves.
Lastly but I'm doubtful on this one is that you have fungas knats which can cause all of the above problems as they're larvae eat away at the roots causing no end of problems
Hope this helps and I've labelled some pics for you
Fungas knats
Fungas knats
light/heat burn
nitrogen toxicity
nitrogen toxicity
nute burn