Have we created mutant flatworms?

[myinvalidname]

I have a 3 gallon pico tank setup that managed to get some acoel flatworms. I picked up some flatwormexit, removed some invertebrates from the tank, removed all carbon and filtration, and dosed 4 drops of FWE. I watched for the next 30 minutes as a dozen or so FW continue to move around on the glass. I dosed another 6 drops for a total of ten drops and watched. Nothing. Happened. I added another 10 drops of FWE for a total of 20 drops.

I have nothing left in the tank, so I’m not worried about killing anything at this point. So I’m just raising the dose to see what happens. I’ve dosed 8x the recommended amount and I still see them moving around the glass.

I’m wondering if over time the hobby has created FWs that have a significant tolerance to change he active FWE ingredients, similar to antibiotic resistance.

 

[ca1ore]

Probably not. Scale of use is not really comparable.

 

[ZoWhat]

At 3gals... I would think manual removal might be a good option.

Go the the Dollar store and get a couple of different angled tweezers.

Manual removal is going to take several attempts over the course of days

 

[myinvalidname]

At 3gals... I would think manual removal might be a good option.

Go the the Dollar store and get a couple of different angled tweezers.

Manual removal is going to take several attempts over the course of days

I’ve used FWE in the past with limited success. I figured that I would take the opportunity to experiment in this small tank with FWE and see what happens. I’m not looking for a solution, I’m just shocked that they are still moving around on the glass.

 

[andrewkw]

I think it's more likely flatworm exit is getting weaker.

I am a big fan of the product and have used it several times over many years. Recently I treated my frag tank. I got a good 90-95% on the first dose (I always overdose the product). I dosed again about a week later, then dosed one final time. Still I'm seeing a couple of stragglers. I think when I get a new bottle I will just dump the whole thing in. Each bottle treats 300 gallons and my frag system is slightly under 100 so in theory I should get 3 full doses.

The other possibility is a few flatworms are finding some safe pockets where the flatworm exit is not reaching. This could also be true in your pico since flow is problematic in a pico. When I get around to ordering another bottle I'll turn up the flow and make sure everywhere gets exposed.

 

[Sarah24!]

Hello,

I have not tried flatworm exit yet, but (now I have a full reef so I could only do this with softies), but I dipped them in fresh water and they hate fresh water. I saw three soft corals and I couldn’t see very many. But when I dipped the soft coral in fresh water I mean hundreds came off it was crazy and that’s per coral. I probably knocked 1,000 off of three soft corals and my tank is 240 gallons. So there is a lot more I just can’t see them on the rocks or any other coral.

Some wrasses will gladly eat them up and keep them at bay. You may try a different bottle of flatworm exit or a different brand. If you just have live rock, another way is to dip the rock in like coral rx or coral dip that will usually knock them off. But you need to run carbon they are super toxic when they die to fish and corals.

 

[myinvalidname]

Again. I’m not looking for advise. And I apologize for not being explicit before. I have three tanks running right now, including this little 3 gallon. I wanted to test FWE on my FWs. Like I said before I have experienced mixed results before dosing FWE and it’s not an adult vs egg issue. I’ve seen adults not die during dosing. So that’s why I wanted to do the experiment of how much of an overdose is required.

So update: I did a 10x dose over about 2 hours. I did nothing for 24 hours after that. Then I changed 80% of the water. One day later, I see five adult FWs on the glass. And yes this is a new bottle of FWE.

I am convinced that some FWs have developed an immunity to FWE. There is no other way to interpret the results of this experiment.

And I don’t want this to come across wrong, but I do have a PhD in experimental science. So this no a hard experiment to run.

 

[jda]

It is possible that the strong have survived and continued the population. It is also possible that you do not have the typical red planaria that the levamisole kills so easily... there are many types of flatworms that it is not effective on (much to the dismay of many).

Do not assume that if you have some that they were all the same kind.

BTW - you can make your own FWE with some levamisole commonly available in the livestock dewormer called Prohibit.