Me again. The tank has already a month or so. Still have an algae, but this algae attacks only substrate surface, walls of the tank and dead leafs. So, no reason to panic.
I was adding the CO2 from citric acid+soda bottles for a month and it became very quickly a mistake. The filling lasts only a weak, so I already have made 4 fillings. Estimating one filling as something over a 1.7 $, multiplying with 56 weeks get me a huge amount of money - 95 bucks. That's one problem, the another one is that regulation on those cheap sets sucks. Its almost impossible to set stable count of bubbles. The regulation at these low amount of gas sucks and is oscillating about nothing and the right amount, depends on the pressure etc. So I often have set the right amount and later I find the diffuser doing nothing.
So I ordered profi solution - classical CO2 set with steel bottle 2 liters, regulation valve, needle valve, steel reverse valve (better than cheap plastic I got, it can leak) and EMF to turning off gas in nights. Well, it costed me something ( 160 $) but its build from quality Camozzi components. Also, the filling will be probably many times cheaper, the filling of this bottle should be around 4 bucks / per 3 months maybe.
And because of that, I will be also able to add some fish into tank. I wouldn't risk that with previous technique of CO2 enrichment.