Plants not growing/thriving
Here are my specs
75G - 48"Lx21"H width doesnt matter
Finnex Planted+ CC series 48" light (12 hrs of light)
Seachem Flourite substrate - about 2.5-3 inches
GH - 4
KH - 3
Plants - Amazon Swords, MicroSword, Monte Carlo, Lugwidia (I think) and Java Fern
They are in the tank for about 3 weeks now. Tank is still cycling (fishless). I am in nitrite spike step where Ammonia doesnt remain but Nirites donot get consumed fully. So the Nitrates are high 80ppm.
CO2 - DIY CO2 injection (12 hrs of injection along with light)
Seachem Flourish - 2 times a week
Seachem Phosphorous - 3 times a week
Seachem Potassium - 3 times a week
Seachem Iron - 3 times a week
All the plants have melted and come back about a 1.5 weeks ago. There is some algae in the tank. I think its because of high nitrates and since I add ammonia for cycling. I dont see growth for micro sword and monte carlo specifically. Please help!