Rust Brown Flatworms resistant to Salifert FW Exit

[The Velvet Sea]

I've eradicated rust brown flatworm (these are not AEFWs, they are the stick on the glass and lay on the rocks FWs) infestations in other aquariums in the past using salifert flatworm exit. I currently have a very small number of flatworms in my reef aquarium that seem to be resistant to it though. I siphon as many out as I can (which now isn't many since I don't have that many overall) and use flatworm exit (even doubling the dose on occasion) but there are still a few survivors.

My first treatment when the flatworm population was larger was to dose the tank and let it sit overnight with no mechanical or chemical filtration running. The next day I did a large 30-40% water change and then re-dosed and let the tank sit for at least week. Now I just dose 24 hours before my weekly 5% water change and then I redose afterward. By now I've dosed a large amount of fw exit and some of them are still hanging around.

They aren't causing any harm currently, but I know what they can do if allowed to remain and I can't seem to completely kill off what I have now. My livestock has been fine throughout it all.

My questions are:

Has anyone battled rust brown flatworms that were resistant to salifert before?

Does anyone know if salifert fw exit expires? I'm going to pick up a new vial today and I am hoping that could make the difference.

[pkat424]

Not sure about salifert, but I've had success using a fish combo of a six line wrasse and a spotted mandarin. Cleaned up my "rust" colored flatworm problem in about a month. My tank (24g) has since been free of flatworms for a few years now.

[NaCl_pro]

I've heard that these planaria (sp?) will build up an immunity to the salifert flatworm exit. The problem is that the flatworm exit kills all the adults but the eggs that haven't hatched are generally unaffected and then mature with a resistance to the original chemical. (sort of like getting vaccinated when we are young.) I've found that an additional dose within 3-4 days (when the eggs should hatch) usually does the trick.

Otherwise, the six line and spotted mandarin are a good natural combo as long as your tank can support them.

What are you using to siphon them out? I used a piece of rigid air line tubing, heated it up and put a bend in it to help get a better angle and siphoned them out with that. a good trick i picked up from a guy on here was to run the small siphon hose to a mesh bag in the sump so you can siphon all day and not have to do a water change.

I would siphon as many as i could see then hit it with an increased dose of the flatworm exit.

Good Luck!!

[SDguy]

Take a container with known volume and fill it with tank water. Siphon a bunch of the FW into it. Dose the container dropwise with FWE until they are 100% dead. This will give you a general idea of how much FWE you need to kill the remaining FW.

[crvz]

Take a container with known volume and fill it with tank water. Siphon a bunch of the FW into it. Dose the container dropwise with FWE until they are 100% dead. This will give you a general idea of how much FWE you need to kill the remaining FW.

I've done this myself and it's a good approach. I was actually doing it with zoanthid eating nudis, for which I'd read FWE works (and confirmed it). For my case, I ended up at about twice the recommend dosage, which did irritate some of my corals. I didnt lose anything, but take care if you plan on proceeding with that approach.