We have been experiencing some issues with invasive brown clove polyps in our 6 foot main reef display, it wasn't terrible but the polyps were starting to spread and they were surrounding a nice colony of Mega rainbow zoas so we thought it was about time we did something about them.
Removing the rock and scrubbing the polyps off doesn’t really have an effect, we know this as we had a single easily removable coral which was surrounded by the polyps (presumably how they got into the tank in the first place) and despite numerous scrubbings out of the tank the polyps just grew back.
Our online researched showed there may have been some good result using Panacur small animal wormer, as experienced reef keepers we worm our livestock quite often and we know the powdered wormers used for Aquarium and Pond livestock are also often the same as used for other small animals we looked into this method of treatment further.
Before diving in and treating the whole tank which is a risky business considering the amount of coral we have in the tank we decided to run a sample test on the single removable coral, this coral was removed from the tank along with its clove polyps and placed in a large jug containing tank water. A small amount of the panacure (0.2ml) was added and the coral was left for a couple of days in the jug (We hung the jug in a weir to keep it to tank temperature)
After a few days it was noticed the polyps had shrunk up and vanished with no ill effects on the host coral (in this case the host coral was a lovely coloured lobo) we put the coral back in the tank to observe any effects.
The result, success, after several weeks of observation the clove polyps did not return, HORAHH
The Tank Dose
We felt more confident in the dosing of the tank at this point, the test coral had seen no ill effects and the clove polyps were gone, it was time to dose the big tank.
Firstly we had do a little preparation, we knew from our reading that the treatment would adversely affect other soft polyp corals, this included the Green Star Polyp that we had growing on the back of our display tank so we knew this would have to be removed, so we carefully scraped it off the tank and placed it in another sank for the time being.
The treatment was added to the tank (1ml for the 550 litre system) and we sat back and waited. The plan was a 14 day treatment to ensure all the polyps were gone.
Initial observations showed that most of the brown polyps retracted into little balls, great its working... but we also observed our two toadstools in the tank were also retracted and unhappy, but we kind of expected one or two corals may react to the treatment.
We left the treatment to continue and after a few more days to a week in one of the toadstools looked so sad we removed it from the tank completely, but it failed to recover.
As we got towards the end of the 14 day treatment we noted we had lost a few head of duncan colony, initially this was put down to the clownfish trying to host it and being quite aggressive so we continued towards the end of the 14 days. At this point we noticed that the second toadstool looked unrecoverable and it was directly under the Duncan heads we had lost. So this would indicate the Duncan coral loss was actually down to the treatment affecting the toadstool which in turn causes issue with the Duncan which was touching it. Urrgh not what we wanted. We also note our cheato reactor didn’t do well during this time.
Once the 14 days was up, we had lost two toadstools, and a few heads of duncans, so that’s not a complete disaster considering it was an experiment. Carbon was added and we did a reasonable sized water change on the system (it usually runs without water changes) we also re stocked the cheato reactor.
We have since re added our GSP, unfortunately this didn’t fare well so it was removed again, it looks like some element of the treatment is still in the water so we will do further removal with carbon and extra water changes to try and ensure all remnants of the treatment are gone.
But what about the brown polyps?
Well it looks like the majority of them are gone, any that were freely visible on the rocks have gone, completely, however there are a few brown polyps remaining and these are the ones that are in between zoa polyps in our colony, its almost as if they have managed to hide from the treatment between the zoa heads.
The treatment itself does work, but if you’re going to treat your entire tank remove ALL SOFT CORAL (although zoa were unaffected) because they simply won’t survive the treatment, if you can remove the rocks or coral where the brown polyps reside this is a must safer option. Because it was so harmful to most of the soft corals in our system, we have to assume you can use the same treatment for removing blue clove polyps and other invasive species as long as they are not hiding away from the treatment
All our other corals were unaffected, hammer corals, torch corals, SPS, monitpora, plating montipora and other lps were all 100% fine, the treatment wasnt long enough for us to observe if there was any affect on growth during that period but growth since appears normal.