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Your tank looks very good, minus the ugly algae
This is nothing unusual. If your tank is relatively new, this is likely diatoms that tend to run their course on their own, and in a short period of time they will no longer be an issue. They consume silicates in the water, and once the silicates are depleted, the diatoms will die out
You may then see some brown, stringy dinoflagellate algae, in fact you may have some already, it's difficult to tell from pics. Dinos are a bit more of a stubborn pest, but they too often just run their course and go away, though it takes much longer (many (sometime very many!) months) for that to happen. For that reason, reefers do take steps to counter the dinos.
There's more than one species of dinoflagellate algae that we see in tanks, and the "best" or maybe the most precise way to treat them is to first identify what you're dealing with under a microscope. You don't need a laboratory quality, scanning electron microscope, many reefers literally use a $30 kid's toy microscope. Hold your phone's camera up to the eyepiece for surprisingly good pictures that you can then post here on R2R for confirmation of what critter you're dealing with. If you have more money to throw at this purchase, decent Chinese made microscopes from brands like AmScope and Swift can be had for the $100-$300+ range, depending on what features you want. You don't need ultra high power 'scopes for reefing purposes at all.
All that said, there are some basic steps you can do to help with Dino's, things us cavemen did before we had things like microscopes for aquarium use
Dino's tend to pop up when nutrients (nitrate and phosphate) bottom out (go to zero or very near it), so it can be a good idea to monitor and if needed adjust the concentration of these parameters so that they are both above zero for sure. Additionally, manually siphon out what you can, and increase flow. There are some clean up crew critters that can help with Dino's and other algae too.
Here's a great post form the late
@Miami Reef on dinoflagellate control:
I'd like to give my perspective on how I approach dinoflagellates in reef tanks. They can be challenging to treat and release a lot of toxins. I personally dealt with dinos several times in the past, so I've gained a lot of hands-on experience. I've done a lot of research on them, too. Here's...
www.reef2reef.com
Here's Randy Holmes-Farley's target ranges for nutrients including N&P if it's helpful too:
Folks confused by all the different opinions on nutrient target ranges might want to check out this new article. I do not eliminate the confusion. I just give a detailed rundown of why it exists for logical reasons...
www.reef2reef.com
I hope that helps; good luck!