Algae growing in GFO and Carbon Reactor?

[Exus]

I think algae is growing inside my reactors, greatly affect flow. Is that what it is? There is only a small light I turn on to do maintenance, so I don't understand what the cause is.

This has been happening for the last couple of months, I would clean and put in new media, then maybe 10 days later, it'll look like the image below. Feel as though I'm wasting a lot of partial media.

I also started carbon dosing about 3 months ago, I'm suspecting it, but I don't know why.

My nitrate is 10~ and phosphate 0.05.

 

[Aquajamin]

I think algae is growing inside my reactors, greatly affect flow. Is that what it is? There is only a small light I turn on to do maintenance, so I don't understand what the cause is.

This has been happening for the last couple of months, I would clean and put in new media, then maybe 10 days later, it'll look like the image below. Feel as though I'm wasting a lot of partial media.

I also started carbon dosing about 3 months ago, I'm suspecting it, but I don't know why.

My nitrate is 10~ and phosphate 0.05.

That seems quick for algae to grow with no light? Maybe the media is tumbling too vigorously and the mush is depositing on the walls of the container?
When I first started using GFO, it dissolved in a week from too much flow.

 

[mdb_talon]

If it is not exposed to light regularly and it started after you started carbon dosing I would be more inclined to think that it is bacteria rather than algae.

 

[Muffin87]

There is only a small light I turn on to do maintenance

I'd steer towards something else then?
No chance that's detritus?
Or bacterial sludge? That'd be more in line with carbon dosing.

Maybe try temporarily using some of these filters. If you mechanically filter the water going into the reactors, you could determine if it grows in the reactors, or gets stuck in them.
https://reefbuilders.com/2021/07/20/prefilters-are-a-must-for-any-dosing-pump-pulling-live-water/