ID and treatment for red stringy/wiry algae... please?

[Starganderfish]

I'm having issues with a dark reddish hair/turf algae kind of thing growing on one of my main base rocks in my tank.
It's a dark red/brown, seems to be individual hair-like strands, and it's spreading over the rock. I can manually yank it out but it tends to leave runners behind and grows back pretty quick. My bullet Goby likes to dump the sand he's sifted on this spot so the algae ends up with a lot of sand in and around its roots which is helping it to grow and spread.
Tank is a 20 Gal Waterbox AIO. No skimmer (too hard to maintain salinity in a small tank with an ATO and a skimmer)
I've moved over to a Santa Monica Algae Scrubber in the back chamber, but the algae doesn't grow much at all in the scrubber yet. Been about a month and a half since I installed that. Previously just grew Chaeto in the back. Some filter floss changed every few days, a bag of Chemipure blue.
I use an AWC that does daily 1-2% water changes, & an ATO for top ups.
I feed 1-2 cubes frozen every second day (give or take)

It's a mixed LPS reef (zoa's, Gonio's, Alveo, a small torch and hammer, a Blasto and an Elegance) with a Maxima clam and a BTA.
I'm a little overstocked with a pair of clowns, a small Rainford Goby, Bullet Goby and a Lawnmower Blennie, pair of coral banded shrimp, a heap of zombie snails, a few Ceriths, Turbos and Trochus and a single yellow leg Hermit. (I struggle to find hermits that don't feast on the snails). But the tank is fairly stable, everything is growing pretty well and seems happy.
The Lawnmower Blennie happily eats frozen food as well as dried nori, but doesn't pay any attention to the nuisance algae.
I don't get an insurmountable amount of algae on the glass (scrape it down once or twice a week)

Nitrates and phosphates are a little high at 20 and 0.5 respectively (Measured with Hannah Checkers) The Algae Scrubber seems to be getting off to a slow start and I think that's caused my nutrients to drift a little high, but the Algae's been around since well before that.

1) What type of algae is this?
2) Whats the best way to get rid of it?

The Algae Scrubber hasn't been doing much yet so I can pull that out for a bit and use chemical treatments (as long as it's safe for everything else in the tank).
I'm also happy to try biological methods but I'm in Aust so available CUC options are a little limited.

Appreciate any advice

 

[Mark Novack]

See Geledium. Crabs mithrax, tuxedo or tripneustis urchins, sea hare. It roots deeply into the rock. Hard to get out. Sterilizing the rock is the only 100% solution.

 

[Starganderfish]

Anyone know if Abalone eats Gelidium? Tuxedo’s are tough to get in Aus, and so are sea hares. They only come up in stores very rarely.
Collector Urchins grow pretty big for a 20gal nano, and tend to pick up and move stuff a lot. Emerald Crabs are simply not available in Aus.

I had an abalone for a while and he was a monster cleaner, scouring the tank every night. He was way too big for the tank though (dang online shops) but he navigated the whole thing without knocking over any frags or making any mess. Sadly he ended up starving and a couple months after that the gelidium appeared.
I can try and pick up a much smaller one to help nip this in the bud and then try and return or on-sell it if it starts to Outgrow the tank. They’re a lot easier to get in Aus.
My reading suggests that macro algae like Gelidium and Gracilarius are often used as Abalone food by folks farming them for eating.

 

[Subsea]

I have that on some Gulf of Mexico diver collected live rock. If you can remove the rock from the water, use hydrogen peroxide and apply with a toothbrush as a spot treatment. When red macro begins to die, it turns iridescent orange.

Gelidium, Red Wiry Turf Algae​

Many species of short creeping red algae exist so the hobby generally lumps all of them under the heading "Gelidium", (the genus that is home to many of those species), and the common name Red Turf Algae, or Red Wiry Algae.

 

[Starganderfish]

I have that on some Gulf of Mexico diver collected live rock. If you can remove the rock from the water, use hydrogen peroxide and apply with a toothbrush as a spot treatment. When red macro begins to die, it turns iridescent orange.

Gelidium, Red Wiry Turf Algae​

Many species of short creeping red algae exist so the hobby generally lumps all of them under the heading "Gelidium", (the genus that is home to many of those species), and the common name Red Turf Algae, or Red Wiry Algae.

Thanks. Unfortunately this is on one of the main substrate rocks of my scape. I’d probably have to remove about 70% of my rock to get to the piece and it forms about 2/3’s of the base of the rock pile.
I’d prefer not to disturb my BTA any more than necessary, if I can manage biological control.
If it doesn’t work, I’ll remove it and manually de-foliate, but at that point it’s basically a full tear down and rescape of the tank.

 

[Subsea]

I have used hydrogen peroxide in tank with no ill effects when used as a spot treatment. In the case of pest anemone like aptasia, I use a syringe to inject peroxide into pest biomass. In the case of nuisance invasive soft macro, I have used toothbrush replenished with peroxide to have little impact on larger reef tank, yet I have had little success with intank eradication of Gelidium.

 

[Starganderfish]

I have used hydrogen peroxide in tank with no ill effects when used as a spot treatment. In the case of pest anemone like aptasia, I use a syringe to inject peroxide into pest biomass. In the case of nuisance invasive soft macro, I have used toothbrush replenished with peroxide to have little impact on larger reef tank, yet I have had little success with intank eradication of Gelidium.

Thanks. Peroxide actually sounds manageable.
I've had great success using Peppermint shrimp to remove Aptasia (totally gone within a week and never returned) so biological control can be effective, but it's definitely hit and miss.
We can get Turbo snails here in Aus but they are not the Mexican Turbo (Truubo fluctuosa) they're a local species, which is still good for algae, but no idea if they are great for this specific outbreak.
I like the idea of spot-applying a little H2O2

At this stage I'm thinking:
Manual removal as best as possible,
Spot application of H2O2 to the affected area,
Turbo snails and a small Abalone to try and keep it down, prevent it returning.

It doesn't look like I'll be able to get a Tuxedo anytime soon, so I'm thinking an Abalone is worth a try.

 

[Starganderfish]

Well, that's been a disaster. Was unable to get a small Ablaone - they're all massive - so I picked up some Hermits and a short spine urchin. Hermits disappeared in the tank and have been doing hermitty stuff - no effect on the algae.
The urchin's been in there for about a week and a half. No interest in the algae, even when I plonked it right on top of the stuff. Worse, it's completely collapsed my entire scape three times.
Being a Nano, I foolishly haven't stuck all the rocks together solidly, preferring to be able to re-arrange. But everything was solidly wedged in place, and has been solid and motionless.
Now every morning I check on the tank and find it a loose pile of disordered rubble. Several corals have been repeatedly buried into the substrate, my nem's been wandering all over the tank and my clam ends up precariously balanced on a pile of rock. If it wasn't firmly attached to a clam cradle, it would have been lost under the rock by now.
I really have no choice now.
I'm going to have to practically tear down the tank, re-arrange everything and epoxy my scape together,
On the bright side, I'll be able to use that opportunity to scrub off the algae and treat with peroxide, hopefully getting rid of most of it.
Maybe if I can kill off the majority, and urchin-proof the scape, then the spikey little SOB can keep it under control without demolishing everything.
Going to be a long day in the tank this weekend.

 

[Starganderfish]

Urchin went back to the shop. Too destructive in a small tank.
I basically did a soft tear down, draining a lot of water, removing all live rock and dripping peroxide over it using a pipette. Re-assembled the tank, put everything back and over the course of a couple of days the gellidium died off.
Nothing seemed to want to eat it when it was alive but it dissolved away pretty quick.
I just spotted some strands returning on a piece of rock, so I'll be pulling that and treating it individually. I think it;s going to be close watch and spot treatment for the foreseeable future with this.
Everything survided though and the tank is back up, and looking relatively healthy.

 

[Starganderfish]

Three months on the Gellidium returned with a vengeance and was again getting out of control. Repeated attempts to control with spot treatments of Peroxide in the tank water proved completely ineffective - It fizzed and bubbled for a while, with lots of bubbles coming off the algae but it didn't affect it at all.
Then I read some advice that was a total "Duh, of course" forehead-smacking moment though. I really should have figured it out for myself.
I mixed up a large batch of fresh Saltwater to correct salinity and heated it to temp. Then I moved the AWC level sensors and used the Auto Water Change system to drain about 90% of the water out of the tank. Left about two and a half inches (just below the level of the lowest patch of Gellidium). It was enough for the fish to lurk in, (looking super grumpy), while the corals, anemones and clams are all fine with relatively short exposure to the air.
I dripped Peroxide on the exposed Gellidium, left it for ten minutes, then reversed the Auto Water changer and refilled the tank with fresh Salt Water.
It took ages because the AWC has an emergency feature where it pauses the process with an alarm if a drain or fill takes significantly longer than previous changes. It's a clever feature designed to save you if a level sensor fails and it tries to take too much water out or put too much in. But in this case I wanted it to, so I had to keep over-riding the alert. I got a little impatient and manually removed and added water with a small container to hurry it along but the process was relatively painless and I pottered around doing other stuff while it ran.
One patch of Gellidium started dissolving within an hour or two and the hermits and even the Lawnmower Blennie had a chomp on it. Two days later that patch is gone. The larger patch higher up in the tank has faded to grey/white and is looking thin and translucent and also appears on its way out. A couple more days and I will hopefully be Gellidium-free again... at least for a while.
Sadly, I think it's going to keep returning, at least until I can do a full tear down, soak all the rocks in peroxide and rebuild the tank from the ground up, but for now, this process is manageable, not TOO annoying and doesn't require me to disassemble the scape. If I have to do it every few months for the next little while, I can live with that We're moving house at the end of the year, so the tank will need to be torn down and transported then anyways. That will be Peroxide soaking time I think.
Till then, at least it's manageable.

 

[Starganderfish]

Three months on, like clockwork, and the Gelidium was back and out of control. Two or three large patches in the usual places and even some growing on the side of the clam!!
Good news is I have the process down pretty well at this point.
Cranked on the AWC, drained the tank down to about 2 inches of water. Manually yanked off the worst of the algae and then generously drizzled peroxide over the remnants. Reversed the AWC and refilled the tank. Took about 3 hours to drain and refill which was a pain but gave me a chance to really scrub the glass and tidy up while waiting.
Gelidium was fading within hours and by the next day 60% was gone completely and the rest was dead or dying. Removing that and doing a massive 80% water change left the tank looking really fresh and clean and everything is super happy. I was worried that adding that much peroxide would upset the tank by the time I refilled it was obviously diluted enough to be harmless.
As an experiment, I have a Tuxedo Urchin coming this week. I tried a Short Spine Urchin a few months ago and it devastated the rock work. Hoping the Tuxedo will be smaller and less clumsy?
Tuxedos are almost never available here in Aus but an online shop had one for only $40 so I figured I’d give it a go.
I can cope with the manual drain and peroxide treatment every three months if I have to but it’s a pain. If I can get something to biologically control it a bit better, even if only to stretch out the period between treatments, it’s worth a try.