Acans being eaten by a red algae


Reefing newb
I wasn't sure which forum to put this in: algae or corals. I have this reddish colored algae that is seemingly eating my acans one by one. I pulled two acan frags and dipped them in seachem reef dip followed by Revive. I then moved those two to a new tank and they seem to be recovering (they were my rainbows). I have two other frags in my tank that are on larger rocks and they are now being attacked. Pics is attached of one. Kind of hard to see.

My main concern is 'what is this stuff?' I've been doing regular water changes but my last two (when the algae really started to take hold) were done when my RO/Di filter was in need of a resin change (PPM read 200). Could that affect it?

I know my nitrates are pretty close to zero. My nems are thriving. :) I'll check alkalinity and calcium and post it up. If I need to test for anything else, please let me know. I will if I have the kit.
Thanks all.


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From your picture, it looks like the sweepers are out. If you had another picture that would help. Yes, change your resin and ro cartridge. It should be 0, my staight tap water has less tds......
This might be a better picture. What the acan looks like is: The center area where the feelers & mouth are have become very sunken in. I have not been able to get them to eat/grab any food. The red slime/algae that I circled seems to have encased itself completely over the exposed skeleton - all along the outside rims of each head. Like I said, a coral dip and revive bath and they are recovering in my 2nd tank, but I don't want to remove all my acans from my DT. :(


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One note: everything else in my tank (including SPS) is doing great. It's only the acans that have been hit by this - whatever it is.
What you are describing sounds like Cyanobacteria but I really can't make it out in the pic. You are getting some excess nutrients in your water via feeding or your RO/DI numbers. I don't know what species anemones you have but once they are established they have the ability to tolerate some nitrates so don't use them to judge your nitrate levels.
Give us some actual numbers on your parameters. If it is cyano then you want to fix your nutrient problem and make sure you have enough flow in the areas it is collecting. You can syphon the red slime out when you do your water changes.
What lighting are you using and how old are your bulbs?
I have (10) 3W LED's (rapidLED) and 4 T5 bulbs on my 29g tank. The LED's only run at about 50% power. The T5 bulbs are all less than 4 months old. I actually didn't have the problem until I added those. I'll run some water tests shortly. My DI resin came yesterday so I need to change that today and do another water change. I'm wondering if I shouldn't do something significant like a 20-30% change.
How long is your light cycle? If you are running them 10-12 hours you can also bump that back a little.

That's your call on the water change percentage. I would rather do a few 10% changes over a short period vs 30% at one time. That way you wouldn't have such a big swing in parameters if something is a little off. Just my two cents;)
My LED's are on the longest - from about 8am until 8pm - but only at 40-50% power. The actinic T5's come on at 8am and run until about 4pm. The aquablue special's run from 10am until 5pm.

I tested my calcium (440ppm) and my hardness (7dKH or 125.3ppm dKH). Not sure if that helps. I will check phosphates & nitrates after lunch. Thanks all!
Test your nitrates and phosphates. Start looking at your food type and how often you feed. Flake and pellet food have a lot of phosphates in them. Symphony as much of the algae out as possible with your water change and then increase your flow to that area.
I may just figured out my problem. My 600gph power head was unplugged - likely for the last month or two. It's on a timer to turn off at night so I never realized it. I'll put up an update in a week or two to let you all know if things have improved. Thanks!!
Fastrd400 - I typically feed pellet or wafers once a day. Only about 4 or so pieces per fish. I supplement 1-2 times per week with krill & brine when I feed my coral.
acans are pretty strong. Have you tried blowing it off frequently with a turkey baster? I'd do that and direct feed it for a while. Maybe it will come back. If its the only thing doing bad I wouldn't change any of the set up,