Hi
@tomerus I can only speak from my experience but I have experienced algal blooms in my setup.
The things I would have done differently from the start are as follows:
1) Ensure that CO2 levels are at 30ppm at lights on every day. I had an issue with a blockage in my regulator which saw me without sufficient co2 until I cleared it. Its one variable you can keep constant fairly easily.
2) Think more about hardscape placement and flow. I've recently changed my lily pipe to a downward facing outlet as opposed to the standard output that flows just under the surface. Not only should that help minimise CO2 wastage (i think?) but it directs flow towards an area that I had green hair algae and staghorn algae recently. It may turn out that the flow suffers somewhere else but this comes down to hardscape placement which Im unable to change now.
3) A dimmer allows for more flexibility when trying to balance your tank. If CO2 and nutrients remain the same, light will be the variable you can alter when you need to, provided you keep up with maintenance. 50% once a week after tank cycling is advised but to be honest, i've had to change it about twice every 10 days. As
@Kimbubbley mentioned, change as much water as you can initially.
Ive asked about the lighting and done some research online and its 269 PAR rating does seem quite high for a 40cm deep tank but again others may know more about the subject. What i would say is think about plant selection. I have some Anubias and Buce that would probably have preferred some more shade but they're doing ok. Again, with a dimmer you're not stuck with that intensity if it does become a problem.
I hope some of this helps, I've been chasing my tail so to speak through inexperience with CO2 injection but I have learnt from it through trial and error and also help from many of the members on the forum. You learn from your mistakes so don't despair if you have any issues, it might not be anything you could have helped after all.
I'd just say enjoy it and don't think twice about asking for help, even if its just to confirm something you think is the case 👍