New too hydroponics

hey all like the title says I'm pretty green to the hydro game. I have two 5 gal bubble buckets going both are showing new roots every day. But the plants aren't exploding like I thought they would. I'm using ro water and AN ph perfect connoisseur. My ph finally settled at 6.3-6.4. Ppm is around 300. Does this sound normal as far as the slow growth?

PH is to high need around 5.7

Even with the ph perfect line up?

That's prolly for soil

OK it is hydro nutes but still too high

Thanks man I'll try dropping it

PPM is pretty low for that size plant. Seedling, 300ppm sure, that looks teen to me you can hit 500-600ppm no problem and she will take off. PH is a bit high....