Tank to Tank Spread of Hair Algae


Premium Member
I recently hooked up a 55 gallon refugium to my 90 gallon Display tank. To start the refugium I put in some Caulerpa On Rock and run 2 8800K PC's for 12 hours at night. I went away for a few days on holiday and when I returned the Caulerpa was covered with hair algae. :lol: My main tank is a year old and never had any hair algae problems.

Question: Is there a risk the hair algae will spread to my main display tank? If so shoud I remove the Caulerpa? What is the best approach to manage this?

Note: The refugium is gravity fed water from my main tank. From the refugium water is gravity fed into a Berlin Sump with oversized Protein skimmer. The return from the sump flows through a 1/3 HP chiller and back into the main. I have filter media located on both the main tank and refugium overflows.

Looking for some advise from you guys with a lot of experience with this.

Thanks in advance for the suggestions:confused:

There is only a trace of phosphate in my water. You might want to check your phosphates to see if this is contributing to your problem. Until I get some better advise (Hopefully from someone on this site) I took the following actions:

1. I placed a phosphate sponge into my sump
2. I purchased an algae Blenny to place into my refuge. The Blenny is in my QT tank and not available for the refuge for another 10 days. (Don't want to introduce Ich on top of this)
3. Added some snails to the refugium.
4. I cut down on my lighting time (in the refugium) until the algae clears. (Note: I starting getting quite a bit of algae build up on the glass of my display tank since setting up the refugium.) :mad:
4. I remove the problem algae by hand daily

Also, I spoke with my LFS about the problem. He does not think the Hair Algae will move to the display tank. So far the problem is not out of control. However, prior to adding my refugium I had zero algae build up in my tank. We shall see...

Any advise from more experienced reefers is greatly appreciated.
Phosphates, are hopefully no longer an issue.

Up until three weeks ago I was feeding primarily flake foods. That has since stopped with the advent of implementing a recipe I found on this site for a homemade frozen food for the tank. I learned that flake food was high in phosphates, so check that one off. Now to your points:

1. I placed a phosphate sponge into my sump.
(I've done this numerous times too. The label's are specific about only letting them stay in there for 48 hours. I don't see effect from this treatment.)

2. I purchased an algae Blenny to place into my refuge. The Blenny is in my QT tank and not available for the refuge for another 10 days.
(I find that my Blenny occasionally pciks at the algae, but he's no fool. When the real food goes in the tank he scrambles like everyone else for his share. )

3. Added some snails to the refugium.
(Now that is something I will try)

4. I cut down on my lighting time (in the refugium) until the algae clears.
(I'm going 24/7, partly because I want the macro to grow and to cut down on the possibility of it going sexual.)

5. I remove the problem algae by hand daily.
(Me too, from the display and refugium. We should have went into stamp collecting.)

My (new) goal is to concentrate on raising the alkanlinity. I'm currently dosing Kalk and will supplement this with B-Ionic Alk. Hopefully this will encourage the corraline and drive off the hair...
So you put this Caulpera in the refugium, went away for a few days, and have hairalgae on the macro algae but no hairalgae in the main tank?

If so.......the stressed Caulpera could leak nutrients/organic and provides a static(non growing) substrate for another epiphytic alga.
These leak out slowly as the Caulerpa dies off some. This can be at very low rates of leakage. Healthy plants leak these also, but the surface is not static.
I seldom find eipihytic algae on Caulerpa species(But have in the past), seldom have I found hair algae.

Spores could have been waiting for the right time to bloom that were already on the macro algae. Often a change will stress out many algae and they will produce spores that settle and grow like mad hoping to adapt to the new conditions.

Tom Barr
How does eipihytic algae look? Does it resemble hair algae? Maybe this is what I am seeing growing on my Caulpera.

The Caulpera looks healthy. Assuming eipihytic algae is growing on the plant what would you recomend I do to manage this?

Epiphytic refer to a plant/algae growing on another plant algae.
Epiplithic refers to a plant/alga growing on a rock, epipdendric, growing on wood and so on.....sorry for the jargon:)

Generally folks don't like epiphytic algae and it causes issue for the infected plant/macro alga. It can appears in many forms(Hair, slime, spots, film, bubbles, other macro algae even).

Getting rid of it? Pruning the Caulerpa, trying to wipe it off with your hands, getting a critter that will eat the eiphytes but not the macro alga(not always easy).
Don't prune it all at once, do it in stages. The Caulerpa will grow back fast.
Some folks use Chaetomorpha (linum?) instead of Caulerpa.
I like Caulerpa ssp generally and for the looks etc.........but for the utility of filtration, other plants/macros should be explored. See what works well for you.

If the hair algae you now have is not causing any issue, I'd just slowly remove it.

Tom Barr