NO3 and PO4, should we dose them with moderation?

[Daveslaney]

I would say the same as Hoggie, your plants look healthy. I would reduce your light intensity see how that goes for a while.
On the last tank i used to get algae on the slow growing plants. I raised the light 10cm higher added some floaters and it went away.
I doubt it is your ferts causing the algae.

 

[Victor]

I doubt it is your ferts causing the algae

I was researching about this and I found my problem may be Ca deficiency. I read the calcium concentration in the tank can't be below 20 ppm. My tap water TDS is only 60! I was adding, per week, 7 ppm of Mg and only 6 ppm of Ca. Now I'll dose 15 ppm of Ca and 3,75 ppm of Mg per week as PPS (perpectual preservation system) sugers. I'll also raise the NO3 and PO4 concentration to 15 ppm and 1,5 ppm per week (dosing 5ppm of NO3 and 0,5 ppm of PO4, 3 times a week). Maybe the ratio between Ca and Mg and their concentration has an impotant role in planted tank. Calcium and magnesium are macronutrients but we talk very little about them, mainly concerning Ca. I got more information about them here: https://sites.google.com/site/aquaticplantfertilizer/home/ca-too-low-high