problems with my new aquarium

[roka64]

I like the aquascaping! It looks like you are working on a nasty case of cyano (purple bacteria) on your substrate.
Can you post your water parameters?
What/how much/how often are you feeding?
How long do you run your lights?

[75Gal]

Can you post your water parameters?
Sorry, what do you mean by parameters. I checked PH and Nitrite levels were Ok but Nitrate was 40 ppm. I managed to bring it down to 20 ppm.

What/how much/how often are you feeding? I feed everyday. one day shrimp (about finger nail size) and another day pellets (about 40 pellets).

How long do you run your lights? From 7am to 11pm.

[roka64]

Water parameters are typically (for FOWLR) ammonia, nitrIte, nitrAte, pH, phosphates (but since you have cyano, you might not see much of the phosphates, since the cyano will gobble it right up).
I would reduce feeding to every other day (I feed every other day and sometime wait an extra day).
So you run your lights for 16 hours a day? If so, I woul reduce to 8-10. I run mine from 2PM to 10PM. This gives me some time to enjoy the tanks when I get home from work.
I would also get some PWCs ready and do a few PWCs to reduce the excess nutrients in the water.