Flushing In Hydro to fix a Phosphorus deficiency? Help!

[WizHigh]

CFL lights 5x 100w 18/6
Hydro using croutons as medium
PH level 5.5 - 6.0
FloraNova Grow/Bloom, Age Old Kelp, Super Thrive


Noticed 2 days ago that 2 of my plants started to slow in growth. There going on 2 weeks veg. Also noticed the bluish color on the outer trim of the fan leaves. Theres starting to be shrinkage of the leaves and also bunching at the nodes. Leaves still feel soft to the touch. So im guessing along with this phosphorus problem theres also zinc and calcium and maybe potassium deficiencies. I added FloraNova Bloom to hopefully fix the phosphorus problem but now thinking should I flush totally and just use PH'd water until new growth and then start adding nutes again? Im looking to buy bat guano and earth juice also (organics). Main thing is im stuck right now. So should I flush or continue with adding NPK and checking the PH of the solution often?

 

[JJ Bones]

Have you considered a foliar feed?

 

[WizHigh]

Yes, I used 20-20-20 ive been doing so the past couple days since ive noticed the bluish tint. Trying to stop it early on. After that it started to get tighter at the node. I also mixed in burpee which is organic all purpose 0-15-11. I didnt want to go over drive on the N so i used this since Grow/Bloom has a high level of N plus using the 20-20-20. After this I wouldve ran out of ideas because I dont want to cause other problems trying to fix one.

Also Ive read that cold solution or temp can cause phosphorus deficiency (lock out). The water when I checked it was a little on the cold side in the reservoir. So I put a heater in it. Also since the came up from grown I raised them in a high temp like 85-90 degrees. Lately its been 80. So I took turned up the temp today and the leaves just got perky. Also IDK why I did but I cut there co2 supply off but I put that back on also today. But i dont think that has anything to do with this deficiency