Diagnose!! Hazy in the day, crystal clear at night

[dhalderman]

Started the tank 2 months ago. Finished cycling, water has been crystal clear for a few weeks, have added some fish and just added my first coral (hammer coral), all doing well. I have a 'haze' that has developed for about a week now, it is not that bad, doesn't even show up well in pictures, but it's night and day difference in person.
I am not 100%, but i'm almost sure it's an algae bloom that blooms under the lights and is removed by skimming during the night. Skimmer pulls out more than usual when the haze is present, and it def looks green...ish. The rocks and sand look unchanged. All fish and hammer coral are doing just fine, coral looking better than it did at the LFS. Glass used to be cleaned about once a week, now every 24 hours, but really after about 2 hours I can see it beginning to build up on the glass again.
I have come to call it the "dust algae". Getting a digital phosphate checker for christmas. Have run GFO since day 1 and changed it again along with carbon at the start of this with no change. 33% WC since the start of it with no change either.
Ammonia & Nitrite 0
Nitrate 5.
SG 1.025.
pH 8.0 to 8.1, API test color is hard to read
Ca 420
My real question I guess is should I expect this to be something that should pass on its own? Being only 2 months old? Or should I investigate further somehow (tips would be nice on that, not sure what else I can do). I'm looking into UV sterilizer, emperor aquatics to be exact. Any thoughts on that? Thanks in advance!

[cloak]

IME these things usually just run their course and then disappear on their own. I wouldn't worry too much about it, especially in such a new tank. GL.

[Lostinthedark]

It probably takes about 6 months for a new tank to cycle through most of its phases. It could be from silicates or maybe your feeding more now that you added some critters and your tank needs to catch up. You'll know better when you test your phosphates.

[lapoolboy]

pH is the one parameter I can think of that fluctuates from day to night. It may be the culprit?

[cloak]

You might want to do a search on bacterial blooms. Cloudy/hazy water is definitely one of the symptoms of this.

[BeanMachine]

What fish did you add? My wrasses like to stir up the sand at times, giving the tank a hazy look temporarily.

Have you tried running a little carbon? That might help.

[dhalderman]

Thanks for all the replies, cloak, I hope it is something that goes away on it's own, hopefully my experiences mirrors your own. I have looked into bacteria blooms at your suggestion, and it would def open up another world of troubleshooting, but the main thing so far that keeps me convinced it's the algae and not bacteria is the difference from night and day. I haven't read anything yet that states or explains why that difference might be seen in a bacteria bloom. Also, I've been ghost feeding when it was fishless cycling, so the amount of food I add into the tank is not much different than it was before I had any fish, just the way it is processed I suppose.
beanmachine, I have 6 fish, here they are and their sizes:
Perc. clown 1"
royal gramma 1"
rainford 1"
tailspot blenny 2"
firefish 2"
clown goby 1"
I rinsed the substrate really good in the beginning, and have kicked it up myself when fixing rocks, adjusting powerheads. It settles pretty well so I don't think it's that either. They are all pretty small so I don't have to feed much. Maybe half cube of Hikari mysis a day. Quarter in the morning, quarter at night. But i'll def be waiting for this issue to clear up before adding anything else.
P.S, tank is a 70 gallon with proflex sump model 3. SCA 302 skimmer. 75 pounds live rock.