Help - New Algae bloom in old tanks - lots of photos

[Steverd]

I need some advice for a new algae bloom in my 50G Low boy frag tank.
It's been running for at least 5 years. the last month diatoms appeared and now hair algae.
No fished added - I have two missing peppermint shrimp - maybe they died?
Normal CUC I get from Reefcleaners for the tank size, Maybe Its time for more.
But do my pictures give you any clues?

Salt: Instant Ocean - I switch to that 6 months ago to save $$$ (What was I thinking?)
Phosphate - 0 - Hannah checker (see photo)
Nitrate - 0 - sea photo
TDS out of my BRS RO Unit is 0 - see photo
PAR is 120-140
I have been running two skimmers for about a year, since I could keep Chaeto alive
(I order a new batch this morning and will try again)
Might be over skimming?

ALso photo of the frag tank (Sand has been there for 2-3 years)
and the overflow with algae growing on it.
Fish: Two Clown fish, a small tang - maybe peppermint shrimps? Can't find them.

I plan a 40-50% water change today if I find different salt and have an ICP test on the way to
send out a sample.

Any and all advice is appreciated - Thank you

 

[Dan_P]

What happened to your aquarium to cause this growth could have occurred weeks or months ago. The Cheato dying might be a hintof what went wrong or be an indication that something was happening before the Cheato started dying.

 

[Steverd]

Just tested my RO/DI water out of the unit and found it's phosphate is 0.11 and my DI Resin was amber color, so I just changed that out with new resin. A good friend said that the Zero Nitrate and the 0.11 Phosphate is likely the cause of the algae bloom. I need to raise the nitrates, add more fish, feed more and/or dose with Nitrate+ by NYOS, I see BRS sells it also. I can also order in some Saltwater Mollies to help,

What your thoughts now?

Thank you so much!

 

[Dan_P]

Just tested my RO/DI water out of the unit and found it's phosphate is 0.11 and my DI Resin was amber color, so I just changed that out with new resin. A good friend said that the Zero Nitrate and the 0.11 Phosphate is likely the cause of the algae bloom. I need to raise the nitrates, add more fish, feed more and/or dose with Nitrate+ by NYOS, I see BRS sells it also. I can also order in some Saltwater Mollies to help,

What your thoughts now?

Thank you so much!

The funny thing about this train of thought is algae consume nitrate to grow. So, low nitrate causes an algae bloom, and adding more nitrogen makes it go away.

 

[Steverd]

The funny thing about this train of thought is algae consume nitrate to grow. So, low nitrate causes an algae bloom, and adding more nitrogen makes it go away.

Yes, I don't understand that. What is YOUR suggestion?
Any advice is welcomed. Thank you

 

[Dan_P]

Yes, I don't understand that. What is YOUR suggestion?
Any advice is welcomed. Thank you

One perspective is that If the coral are happy there is only a visual issue. Is coral growth good?

 

[Steverd]

One perspective is that If the coral are happy there is only a visual issue. Is coral growth good?

Yes, this is mainly a frag tank, 90% Zoanthids and they are growing and spreading, etc just like always.
Also a few Montis growing good too. And that big Orange sps coral growing in the middle (see tank photo)
What next? Thank you

 

[Dan_P]

Yes, this is mainly a frag tank, 90% Zoanthids and they are growing and spreading, etc just like always.
Also a few Montis growing good too. And that big Orange sps coral growing in the middle (see tank photo)
What next? Thank you

The hobby uses the presence of nitrate as an indication that there is more inorganic nitrogen present than the system can consume. With no detectable nitrate in a system, there is no such information that your coral collection has sufficient inorganic nitrogen. With increased algae growth, there is the possibility that the coral will begin to starve. You don’t mention how you feed the coral or ensure they receive sufficient nitrogen. I feel the next step is to decide whether your current coral growing program in the presence of increased algae still supplies sufficient inorganic nitrogen. If not consider dosing ammonium chloride, though start with a low daily dose. Randy Holmes-Farley has provided suggestions on a daily dose. As for the algae, if it is algae and not cyanobacteria or hair algae covered with cyanobacteria, I presume the snail is an inexpensive way to keep the algae in check.