Algae growing in my tank - what do I do?

Hi everyone,

I'm starting to notice some algae growing in my tank. Initially it was green and now it appears to be flipping to brown.

The tank is relatively new, about 5 weeks old. It is fully cycled and my water levels are good - nitrite and ammonia are 0 and nitrates around 10. PH is 7.8.

I have a two filter system and also have a common plecostamus in the tank right now that I'm looking to re-home; he doesn't seem to be touching any of it. The tank is 55 gallon (too small for him). Right now we just have some small barbs and tetras in the tank. I also have a LED light across the top; we usually leave it on for about 8 hours a day and try to limit it to anything more than that. Here are some pics.

What do I do? I'm hoping to not have to take all of the decorations out once a week and scrub them/clean them. Is that my only option?

By the way if it matters my tank is around 78 degrees and the light is LED. It’s a ni-crew light. This one, to be exact:

https://www.amazon.ca/dp/B01M68U638/?tag=

If you don't have any live plants then you'll always end up having some algae. As long as you're providing light and nutrients then algae will grow.
If you don't want live plants, you can minimize algae growth by

• dimming your light or reducing the amount of time the light is on.
• Not overfeeding your fish
• Manually removing the algae
• Introducing some snails