Tomorite liquid tomatoe fertilizer

I am growing 3 Short Rider autos and the plants are looking well.Its been just over 6 weeks since they were potted and they are just over 1 foot high and showing signs of budding.I am using a grow tent and a 250watt hps light but have not yet added any nutes..I was given a Tomorite liguid tomatoe fertilizer made by Levington and was wondering if it would be a good idea to start using this as im on a strickt budget (not alote of money).It says on the bottle `Dilute 20ml in 4.5 litres of water (1 gallon).
Any advice would be very welcome.

What are the nutrient levels in it?

I just read the back of the bottle and its says low nutrient fertilizer.It doesent give you the amount of nutrients..Sadly.