Back wall covered in algae - OK or not?

martin.a

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Hi Guys,

Back of my tank is covered in green algae. Should I leave them be or remove?

Long story: The algae started growing rapidly about 6 weeks ago. Than Amphidinium dinos hit. The algae, and everything else got totally covered in them. Now the dinos are mostly gone and my 'back wall bush' is green again. The dinos eliminated almost all my copepods and these algae are their last refuge.
Removal of the algae would be a messy affair, but certainly doable. But should I do it? Or allow the ecology of the tank to decide?

Here is how about 80% of the back wall looks like:

 
The ecology of the tank may never resolve this issue if you don't figure out what's causing it. Dialing in whatever is fueling the algae(excess light, nutrients, etc.) and adding aggressive algae eaters would be a good solution. Removing it all at once and making a mess isn't worth it in my opinion.
 
I would remove all the algae and keep the back panel clean. Even if you scrub once a week goign forward that is enough to keep the back free of algae and other growth.
 
This is a new tank, about 4 months old, so algae were expected.

I keep a bit elevated macro nutrients now - NO3 ~ 20 ppm, PO4 ~ 0.3 ppm. PO4 is higher than I would like it to be, but I would rather not intervene at this stage.

Gold ring cowry, trochus and astrea snail are grazing, the light is kept in blues and is low and set short.
 
With that much on there I would scrape it all off. Keep it clean until Coralline algae shows up.
 
I would remove all the algae and keep the back panel clean. Even if you scrub once a week goign forward that is enough to keep the back free of algae and other growth.
It would remove the last copepods habitat. They were visible all over the glass before. Now, they are only left on the green. I started culturing and dosing, but somehow it's not going particularly well. I think pods are important, especially given my dino issues.

How to remove? Just scrap and let mat-roller deal with it? Probably scrapping and vacuuming at the same time would be better, but I am not sure how to make it work.

BTW, coraline were starting before the green took over. I am entertaining the idea to get GSP cover the back.
 
Bioload from scrapping without collecting would be tremendous. I need to figure out how to collect the scraps.
I scrapped a bit as an experiment a week ago. It was messy.
 
I had this problem when I first started my tank. I scraped the wall clean and then used a filter sock swishing around in a figure 8 pattern to collect all the debri floating around in the tank.
 
Be cautious removing it because it could be suppressing a nutrient problem and a spike is detrimental.
Agreed. @martin.a , Sometimes the reason you have low nutrients is because it is all bound up in the algae. The algae had to get the nutrients from somewhere. I think a safe course of action would be removing a portion daily and netting it up to not cloud the water, as well as adding more cuc, and making sure filtration is dialed. I wouldn't worry about the copepods, they are going to thrive regardless of the state of algae, even if not as visible.
 

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