They look fried, maybe too much light, probably too much heat.

Howdy Cap'n,

You have a nice little set up there.

OK, first off, you are using a 1000 Watt HPS, so what you are getting is something of a consequence of this. The fact is that you are pushing your plants pretty fast. Some of the the reaction that you are seeing is because the plants are building cells so quickly.

The first question that I have is the HPS the only source of light the tomatoes are getting?

Next, it is unclear from the pictures how the buckets are getting fresh air to the root zone.

Also the buckets seem metal and may be getting warmer than the air. It would be a good idea to check the temperature of the root zone because if the root zone is much over 80 degrees this will create stress.

Here is also a link to Nutrient Troublechart

Please note, though, that nutrient troubles may be the result of something else besides just a lack of nutrient in the solution.

Thanks for the responses.

There is a few windows there in the room to the east. They get some morning sun, not a lot tho. The HPS is brighter than the ambient light for the majority of the day.

Each bucket (5 gal) has an airpump (rated at 2 x 280Lph) with 2 airstones so most of the roots get air bubbles.

Buckets aren't metal they are plastic with foil to stop light getting in (which apparently stops algae growth) - has worked so far). I will test root temp soon.

i thought it might be too much nutrient that caused these symptoms. It's on full strength with the nutes I am using (which are just budget local ones).