Please help ID some algae and hopefully the cause

[trvrstnk4837]

My tank is a 40 breeder, it’s been up for about 4 months er so

My water has been premade Nutri-sea water the whole time with a weekly 4.4 gallon water change

Just checked Nitrate (6.7) Phos (.07) and PH has been 8.2-8.3 consistently

I have 2 36” ReefBright Lumi light pro lights 1 blue and 1 blue white park at the bottom next to the GSP shown is about 90-100 and the top of the scape is around 220-230

I have some brown stringlike coral on the sand and that’s wrapping around some of my coral and would like some help IDing it

Not sure if it’s related but my waters been kinda cloudy lately I was recently vacuuming my sand with every water change but I haven’t done that the last 2 weeks as I found info saying that it isn’t ideal to stir up the bacteria

I turned off blues for the pics


Any help would be most appreciated

 

[Matt Bravo]

Hello there, young tank therefore algae is common and there’s no need to worry much

I believe it looks like dinoflagellates, because of its color and stringy texture. A way to confirm this would be to look at the tank at night and see if the film “disappears” and comes back when lights turn off

Also posting no3 and po4 would help. If they are very low or zero then dinos is definitely a possibility

 

[trvrstnk4837]

Hello there, young tank therefore algae is common and there’s no need to worry much

I believe it looks like dinoflagellates, because of its color and stringy texture. A way to confirm this would be to look at the tank at night and see if the film “disappears” and comes back when lights turn off

Also posting no3 and po4 would help. If they are very low or zero then dinos is definitely a possibility

I checked with a Hanna Nitrate HR and got 6.7 and Hanna Phosphate ULR and got 0.7

Thanks I’ll try and look tonight

 

[trvrstnk4837]

They do go away at night

I watched a BRS YouTube video on the subject that said if they go away at night they enter the water column and a UV can significantly help

This will be here tomorrow, what are your guys thoughts?

 

[Matt Bravo]

Raise nutrients, and I did water changes while lights were out. Not sure if this helped but. I tried using logic, and yes it worked.

 

[bushdoc]

Root cause of this issue is relative immaturity of the tank and ( I presume) using dry rock only. Correct me if I am wrong about second issue.
It look as as if you have green algae, diatoms and maybe also Dinos. Not sure about Dinos. Although there are some ways to say without microscope if you have dinos, the best way is to look under microscope.
Your nutrients are fine.
It takes about a year for a tank established on dry rock to mature and even then there is no guarantee that you will not have algae issues.
Patience, CUC and increasing biodiversity by introducing even small amount of live rock would be my recomendation.