The fishless cycling method on here recommends a higher temp than when there are fish in the tank.
Are you doing a fishless cycle with ammonia or a plant/silent cycle? If it's a plant cycle, you do need to feed the plants and fish-temperature is fine. But if you are doing a fishless cycle with ammonia with live plants in the tank, the ammonia could damage the plants and encourage algae.
Algae is a sign of an imbalance in the tank. In new tanks brown algae is the most common, what you have on your plants is a form of hair algae which can kill plants.
Tomm barr says the two most common nutrients in water that cause algae are ammonia and CO2. New tanks normally have higher ammonia levels as the ammonia hasnt been converted to nitrate yet.
So while algae can be normal in new tank it shouldnt be as much in a tank with plants as plants use ammonia as food.
Adding more plants can help especially fast growing floating plants that are often referred to as ammonia soaks or traps as they consume large amounts if ammonia. Excess light can lead to excess algae. Algae will use any available light including light from outside sources, windows, room lights, tvs ect... Decrease the amount of light from 10 hours to under 8. Algae needs 8 hours continuous light to grow plants do not. I put a towel over my tank once the tank lights go out to keep all outside light off out of tank to decrease algae.
So add more plants, decrease amount of time light is on and algae should decrease.
Also forgot to add if one has plants in the tank then might as well use the fertilizer.
When plants arent provided with the amount of nutrients to grow algae will grow instead.
The goal with plants is that they grow quickly enough to outcompete algae for nutrients, if the plants dont have enough nutrients they wont grow and the algae will.
Id add more than just easy green from Co op. I use it and while it has good levels of NPK it lacks essential micro nutrients that plants need, like calcium nickel and a few others. Get a comprehensive micro nutrient like seachem flourish which provides all the nutrients plants need through water and add with easy green then make sure they get nutrients through roits, from root tabs or nutrient rich substrate. In theory when the plants have all they need they will eat all those nutrients and grow outcompeting the algae.