The presence of nitrate indicates progress.
Try to be patient.
It might happen faster if water was warmer but I wouldn't be concerned.
You're going about it properly.
Since you are fishless, I would add ammonia to feed to feed the bacteria which feed on it. There is a lot of information on this site about cycling which you might be interested in - try searching.
Hey Heath, try lowering your PH using PH Down by general hydroponics, your plants want a ph of 5.5 to 6.5 but shoot for the higher end(6.5)that will help in their nutrient uptake ability. If you are using seaweed extract, follow dosing directions and stay on the low dose end for now. The only ammonia I would add is to pee in the tank once or twice...seriously. Last thing is, add beneficial microbes. If you have a healthy fish tank aquarium or know someone that does, add some of that water, gravel, bioslime! You can use a product called microbelife natural bacterias aquaponic safe to kickstart your micros. good luck man