Odd Algae Problem (Need ID)

[heifinator]

I believe I am having a fight with mermaids cup algae (pictured below). I've been having a problem with the stuff for over a year now and am getting to the point that I am about to swap all the rock in my tank with new cured live rock. I haven't pulled the trigger on this yet and am hoping R2R might be able to provide some alternative strategies that I have not considered yet!

Parameters
SG: 1.025
Temp: 77-78
Ammonia: 0
Nitrite: 0
Nitrate: <5
Phosphates: <0.01 (Hanna ULR Phosphorus)
Calc: 420
Alk: 7.5
Magnesium: 1300

Currently on the tank I am running a cheato reactor that has been working pretty well (running 8hrs every night) and I have been using biopellets for the last ~6 months to combat nitrate levels, also working well.

I had GHA for a while a year ago but adding the cheato reactor, upping the WC schedule (40% every 2 weeks), and running GFO for a short period took it out.

The mermaids cup algae (?) has been completely unresponsive to increased export and decreased import methods. I should note that in the picture it doesn't seem that bad. This is a rock less than a week removed from a h2o2 paste and scrubbing. Everything was completely removed and it grew back out of the rock within a couple days. The stuff is everywhere...

I got Po4 / nitrates down to a point that my SPS began to STN and it had no effect on the alage so I let the levels increase slightly.

I have attempted removing a single rock that I brushed, put a h2o2 paste on, and even blow torched the surface of. The algae dies but new pieces being to grow out all over the rock within a single day.

I've attempted reduced photo periods and 5 days of darkness with no success at all. This particular algae does not seem to respond at all to any of these methods. I've also attempted CuC options but they have no interest in the stuff.

I've fought with byprosis, GHA, dinos, etc and have won those fights which makes this really hard to accept.

As it currently sits the tank is stable, the SPS are colorful and growing (albeit a little pale) but any further reduction in po4/nitrate seems to result in SPS death.

Lets see if anyone has any ideas, otherwise I will be making an attempt to just replace all the rock!

Thanks all.

 

[saltyfilmfolks]

Well short of finding just the right animal to eat it, you may be looking at a more nuclear option. Algae fix, vibrant , fluconazole.

I’d the afflicted rocks are easy to pull, you could do a test , water and peroxide soak for 10-20 or so , rinse.
I’d let the rock set in a bucket a few days though. Last one I did a big rock peroxide clean up , I had some odd stuff happen.

 

[heifinator]

Well short of finding just the right animal to eat it, you may be looking at a more nuclear option. Algae fix, vibrant , fluconazole.

I’d the afflicted rocks are easy to pull, you could do a test , water and peroxide soak for 10-20 or so , rinse.
I’d let the rock set in a bucket a few days though. Last one I did a big rock peroxide clean up , I had some odd stuff happen.

What is the best proceedure for a peroxide dip. I already pulled a rock and used a peroxide / baking soda paste to cover the entire outside of the rock then rinsed. The algae died and scrubbed off but new algae grew from the pores in the rock.

 

[saltyfilmfolks]

What is the best proceedure for a peroxide dip. I already pulled a rock and used a peroxide / baking soda paste to cover the entire outside of the rock then rinsed. The algae died and scrubbed off but new algae grew from the pores in the rock.

Basically a 10-1 ratio , maybe stronger. Drip in and let fizzle.