You have your diagnosis a bit wrong. There is black beard algae but I have never heard of green breard.
Black beard algae (BBA), a type of algae belonging to the genus Audouinella, appears as small, furry black dots or short, reddish or black hair-like strands, often found on hard surfaces, plant leaves, and filter outlets in aquariums.
Although the term green breard algae is used, it is a different thing:
Green beard algae, also known as Cladophora, is a type of algae that appears as short, green, hair-like strands or patches on aquarium surfaces, plants, and decorations. It's often a sign of an imbalance in the tank's environment, such as excessive nutrients, poor water parameters, or inadequate plant growth.
What it takes to keep plants healthy and able to out compete algae is a balance between three factors. Think of it like a stool with 3 legs. As long as all three legs are the same length, the stool is solid. But if one leg is longer or shorter the stool wobbles.
For plants in our tanks the three legs are lighting, nutrients and CO2. Basically, on the type and amount of plants one has, finding the right balance becomes the key. And then there is one more factor involved than many of us fail to grasp as we dive into the world of live plants int tanks, plants grow.
This has two implications. If we start with smaller plants and allow them to grow in, they will usually need some amount more of all 3 things. But, growing plants will ultimately fill a tank and that means we will be pruning sooner or later. And when we do a big prune it has the reverse effect. The demand of the plants go down since we have less mass.
The plants we might use in out tanks fall into a few categories based on their needs. This is usually expressed in two terms. How hard they are to care for which Easy, Medium or Hard. And that usually defaults to light levels from Low to high. CO2 levels in many cases is naturally available and in the low and many medium level plants does not need to be added.
The best help I can offer you here is the Tropica site. They are one of the oldest and largest growers and suppliers of aquatic plants in the world. They have an excellent site where you can learn more than anybody could provide you in the Forum. I would suggest you head to the link below and spend as much time as you can reading and looking there. The two most important sections are the
Guide (it has a section on algae) and then
Plant Care.
https://tropica.com/en/
I have used the Tropica fertilizers in all of my planted tanks for over 20 years. I do this because I realized early on that the success of Tropica over decades meant they had to know exactly what they were doing and who was I to doubt their success. If the fetrs were good enough for the world's best, then they were certainly good enough for me.
I hope the above helps.
