For those wanting to eliminate invasive soft corals from their tanks; I can report that I successfully eradicated Blue Clove Polyps and Xenia from my tank. I used the canine de-wormer medication Fenbendazole without harming my biological filter or killing invertebrates (although Bristle worms and certain snail types are fair game). I think depending on the dosage and treatment time, this should kill kill green star polyps, hydroids and aiptasia. Hopefully more experienced aquarists will provide their input on using Fenbendazole and the risks involved.
Note about worm die off – this treatment will cause bristle worms to die off en masse. Be sure you can remove dead worms when then this happens (which might be impossible for large tanks filled with rock).
Note about Xenia – from my personal experience, since Xenia doesn’t spread like BCP – it would be much easier to manually remove it with a small sharp tool like a screwdriver and slowly scrap the foot off the rock (or just replace that rock with a new one).
After doing exhaustive research on how other aquarists have treated their tanks with Fluke Tabs to kill BCP. I tried in vain to obtain it, or any medication with Trichlorfon (mostly because forum posts suggested it was the Organophosphate that was responsible for killing BCP). Based on this method, I tried soaking some LR in Clout for 2hrs (the only Trichlorfon medication I could find). The treatment irritated the BCP and other corals (Mushrooms, Hammer, Millepora, Acans, and Zoas), but it killed amphipods and bristle worms (although small fan worms survived), and I assume it killed the LR bacteria because Organophosphates are very toxic. I placed the rocks back in the display tank, and the corals revived to a healthy state, so why didn’t Clout Tabs work if Organophosphate was the suguested killer?
I began to wonder if maybe the secondary active ingredient in Fluke Tabs (Mebendazole) was the component responsible. I searched in vain for it, but unfortunately Mebendazole is a prescription medication. Luckily I found an alternative version (Fenbendazole) is available in pet de-wormers (Panacur and Safe-Guard). That’s when I noticed Google returned forum links about Seahorse hobbyists using Fenbendazole to quarantine plants and livestock with the goal of killing Hydriods.
Based on their experiences, I determine a dosage for my tank and experimented with the same rocks in a bucket. After 2 hours the corals seemed kind of irritated, but the blue cloves were pissed off. The dip had no effect on worms and I even saw amphipods happily scooting about. I placed these rocks in the display to see if the corals would revive. After a few hours the corals looked healthy, except for the BCP, but I also noticed Xenia on a nearby rock was irritated.
Because the dipped rock (a full dose) did have an affect on the nearby XeniaI in the display tank, I was very nervous about dosing my whole system. So I took a conservative approach and treated with only a half dose (1mg per gallon).
I felt confident the inverts would survive (mostly because the amphipods survived the test dip). I left two bristle worms in the quarantine bucket to observe them while the tank was being treated. I was worried the treatment would kill my Rock Flower and Maxi-mini anemones (because of reports of it being toxic to stalked hydroids), but they’re very stubborn and would not detach from their spots. I wasn’t worried about the Zoas bexause I think they’re invasive pests too.
Preparation: Various options exist to obtain the medication i.e.
– Buy pure Fendendazole and mix with water.
– Buy some non flavored concentrated dewormer paste.
– Buy 1 gram packets of Safe-Guard dewormer (22.2% Fenbendazole). Grind it into very fine powder and mix into 1 gallon of water. This will make 222mg/gal of Fenbendazole.
Dosage: Recommend dosage is 2mg per gallon of water to be treated (half dose would be 1mg per gallon). A metric dosage would .5mg per Liter (half dose would be .25mg per Liter).
– 1 gallon of water mixed with 1gm 22.2% powder, will treat 111 gallons.
– 1 gallon of water mixed with 1ml of 10% concentrated paste (100mg/ml), will treat 50 gallons.
Risks: I do not know which soft corals will be affected, but any species of the stalked Hydrozoan family may die. Other corals in my setup were not affected, but your results may vary and your tank may cycle, killing everything in it (someone had to say it).
Duration: I used the recommendation for Fluke Tabs of 72hrs. I assumed it’d be the best approach.
2 hrs – fish and inverts acting normal, and the water has become a hazy cloud. My wife wants to know why I’m trying to kill off the pretty blue stuff…
12 hrs – Xenia is pissed off and BCP is irritated. I realized I’ve forgotten about the Sympodium in the back corner. I assumed it will die off, but it can be kind of invasive too. Fish and inverts (even Mysis) are healthy. My blue banded coral shrimp is out scavenging and eating. Bristle, spaghetti, and fan worms are healthy.
24 hrs – Xenia and BCP are shriveled up and appears to be dying, although I’ve seen them recover from worse looking states.
48 hrs – Xenia is definitely dying and detaching from the rock. BCP is slowly melting away into tiny spots. Sympodium is shriveled up. Astrea and Turbo snails have stopped moving, not sure if they’ll survive at this point. The tank is starting to emit a foul fishy smell. Bristle worms in the dip bucket are still alive.
60 hrs – Aiptasia has shriveled up, Rock Flower and Maxi-mini anemones are not happy (shrunken 50% and looking strange). All Zoas have closed up. At this point I decide to start filtering carbon through the sump. All Xenia has completely disappeared, and the BCP has become small white dots.
72 hrs – Rock flower anemones, Zoas, and Aiptasia (unfortunately) are recovering. 50% of BCP has disappeared, with the remaining consisting of a connective layer. Sympodium has been severely harmed, but might survive. Astrea and Turbo snails are still stunned. I decide to start the skimmer and run it wet.
84 hrs – Cloudiness has cleared up, and the fishy smell is gone. The skimmer has pulled out 2 gallons of clear stinky water. Astrea and Turbo snails are still stunned. The tank doesn’t appear to be cycling. Parameters are a little elevated (Phosphate .16ppm, Ammonia .25ppm, Nitrate .75ppm, Nitrite 0ppm). I decide to do a 20 gallon water change. Wife says the bare rock looks ugly and misses the pretty blue stuff…
6 day later – All bristle worms died off en masse. Although spaghetti and fans worms appear healthy. The Astrea and Turbo snails are still acting stunned (I do not expect them to survive). I haven’t seen any Stomatella snails, so I assume they died during the treatment. All Cerith and Nassarius snails appear healthy and unaffected. A particularly nasty Manjo looking anemone has died, although other anemones are ok.
14 days later – Things are looking good; the anemones have fully recovered, but the Astrea, Turbo & Stomatella snails have died off. The tank is going through a minor algea outbreak, but my Tailspot blenny is fat and happy.
Jan 14th 2015 (1 year 8 months later) – The tank is doing fine (same live rock). I recently installed a DIY Avast CS1 skimmer, and added a 10 gallon storage tank to the sump with an additional 40lbs of LR in it. Althoigh I did suffer a system crash when I moved the system to a different house, unfortunately I had to leave everything in Tupperware containers for 3 days and ended up losing 90% of my corals and fish. Luckily everything on the central rock survived. I have numerous SPS frag colonies growing, along with Duncans, Trumpets and rock flower anemones. I had a large variety of corals before and after the treatment.
(1 year 8 months later)
(1 year 8 months later)
Notes: – This was a fairly safe treatment for display tanks and I have no concerns about doing it again. I suspect a higher dosage might also kill Aptasia.
Disclaimer: – You assume all risks when treating your tank using the information contained in this post. Hopefully this information will help someone else safety eliminate invasive soft corals from their system too.