EZG, it's not so much the 7-9-5 numbers that are important here, but those are good numbers to use. It's actually all the micronutes that come in with the NPK, the macronutrients. Some are needed in greater number and are called macros (meaning big), and many other nutes are needed in lesser number (micro, small).
Sounds like very good timing on those plants and a light to boot. HPS in particular is the light to use because you can use it all the way from veg to finish. Put a small fan on them to strengthen the stems. Just enough wind to jostle them a little, so later they won't fall over. You'll have to figure a way to keep the light kind of low when they're small and raise it as they grow.
Other ferts will work fine but DynaGro is a single kind of fert where pretty much everything plants need is in one container. Unfortuately, it doesn't have a very long shelf life. It might be good for about six months. If you can't find it, look for a fertilizer that is a chemical kind of fert, fast absorbing, and has as much of the 16 different nutes plants need for your money. Let me know what you get. You're having a deficiency there, so a small dose of a complete fert would help out. Follow the instructions on how to use it, usually located on the back of the container. Seaweed is fine but it's hormonal and small elements, and it's strong so don't use much of it.