I wanted to note some of my observations from using Brightwell Aquatic's Lugol's solution to rid my live rock of pests. In hindsight, I would have been more intentional about doing this and taken photos and logs, but I figured I'd write something up.
Context:
This is my third attempt at using air freighted live rock. All three orders were for smaller tanks ranging from 10 gallons all the way to 60 gallons. Two orders were from Tampa Bay Saltwater while the most recent one was from KP Aquatics. In each experience, I had a variety of "pests", but the one that forced me to shut my tank down each time was due to Cirolanid Isopods. For those who do not know what this is... it is an isopod that is parasitic and attaches to your fish, typically at night, and sucks their blood. That said, the cirolanid isopod is opportunistic and will feed on other things in the absence of fish (fish food, detritus, shrimp, smaller pods, other invertebrates, etc.). Cirolanid isopods can come in a variety of sizes, going all the way down to near 2 mm, which makes manual eradication very difficult.
Options Considered:
Similar to how Lugol's is used as a coral dip, I decided to use it on my live rock as a long duration "dip" of sorts. I first got a 5 gallon bucket and measured in 3 gallons of saltwater. Then for each gallon of saltwater, I used 60 drops of Brightwell Aquatic's Lugol's solution. I put in a heater to heat the water to 78 degrees and a pump for circulation. I then took the live rock from my display tank and put it in the "medicated" bucket. I left it there for a total time of 5 hours.
I also got a 2nd 5 gallon bucket and made fresh saltwater, heated it to 78 degree and left a circulation pump in there as well. Once the live rock was fully "treated" for 5 hours, I carefully took rocks out piece by piece and move it to the fresh saltwater bucket. In this process, I made sure to use the powerhead in the medicated bucket to blow at the rock pieces prior to taking it out and transferring it to the fresh unmedicated bucket.
I left the live rock in the unmedicated bucket of saltwater for 10 minutes prior to putting them back in the display tank.
Impact of Lugol's On Pest and Other Life On Live Rock:
As soon as I put the live rock in the medicated bucket, I noticed several worms flying out of the rock (due to the circulation pump) and squirming around I could not really see any isopods doing this erratic dance from the top down view of my 5 gallon bucket.
After the 5 hour treatment and once the live rock was removed from the medicated bucket, I got a small glass container and poured the sediment at the bottom of the bucket into it to see what had fallen off the live rock. Below is a list of some things I found:
My Takeaway:
Lugols appears to work in killing a majority of pests, but also kills off your microfauna. I think I can seed my microfauna back using aqua-cultured pods. I also don't think that Lugols makes your live rock "dead" by any means. I will continue my observations over the next 2 weeks to see if a hard cycle is started in my display tank. Use of lugols to rid live rock of Cirolanid Isopods seems only effective to the point that it "stuns" them and forces them off the rock. A higher dosage and a longer treatment time may also impact Cirolanid Isopod death.
One side note is that Cirolanid Isopods may dwell in the sandbed more than live rock. For this reason, I have taken the sand out of my display tank and plan on using new sand after a 2 week observation period to ensure all Cirolanid Isopods are gone. I am also wondering if my encounter of Cirolanid Isopods in every single time live rock was used was in part due to the location of the live rock in the gulf. Could it be that smaller rocks meant for "nano" tanks such as the ones I used the rocks for, come from the lower levels near the sandbed of the ocean where Cirolanid Isopods are more prevalent. This could mean that people who order larger sized rocks or those that are further from the ocean sandbed as less likely to see these pests.
***Disclaimer! this is not a bash on any of the live rock vendors as pests are a given when ordering live rock. The question of this thread is to see possible alternatives to the manual hunting of Cirolanid Isopods and the impact of Lugol's solution on live rock. I am also not a marine biologist, scientist, or even consider myself an "advanced" aquarist. I am simply a regular hobbyist who is extremely tired from hunting for cirolanid isopods past midnight, religiously.
Context:
This is my third attempt at using air freighted live rock. All three orders were for smaller tanks ranging from 10 gallons all the way to 60 gallons. Two orders were from Tampa Bay Saltwater while the most recent one was from KP Aquatics. In each experience, I had a variety of "pests", but the one that forced me to shut my tank down each time was due to Cirolanid Isopods. For those who do not know what this is... it is an isopod that is parasitic and attaches to your fish, typically at night, and sucks their blood. That said, the cirolanid isopod is opportunistic and will feed on other things in the absence of fish (fish food, detritus, shrimp, smaller pods, other invertebrates, etc.). Cirolanid isopods can come in a variety of sizes, going all the way down to near 2 mm, which makes manual eradication very difficult.
Options Considered:
- Going Fallow (fishless): This was not tested beyond 3 weeks due to the fact that the cirolanid isopod is an opportunistic feeder and going fallow would not yield any positive results.
- Going Hunting: This was done in my past efforts and well as my recent endeavor. My hunting method, is fairly common knowledge. This method involves the use of "stinky water" from a piece of raw shrimp, a trap, a net, turkey baster, and a red flashlight. This method was done over hours during lights out, typically between 12am-2am. After many nights of hunting, I was able to capture isopods ranging from 1.5cm to 3mm in length. That said, I eventually gave up as I do have a day job with a family that needs my attention and being sleepless was not a viable long term solution to my isopod problem.
- Interceptor: This medication would be used at a higher dosage than that recommended for treating red bugs in your display tank. While I was extremely curious about this approach and was the primary alternative I was going to test, I was unable to do so because I lacked the sufficient medication to ensure a high dosage amount. My vet would only prescribe me interceptor for my small dog and I realized after spending $60 on 6 month supply for small dogs, all 6 pills wouldn't cut it. Not to mention the medication would have been the most expensive option out of the bunch
Similar to how Lugol's is used as a coral dip, I decided to use it on my live rock as a long duration "dip" of sorts. I first got a 5 gallon bucket and measured in 3 gallons of saltwater. Then for each gallon of saltwater, I used 60 drops of Brightwell Aquatic's Lugol's solution. I put in a heater to heat the water to 78 degrees and a pump for circulation. I then took the live rock from my display tank and put it in the "medicated" bucket. I left it there for a total time of 5 hours.
I also got a 2nd 5 gallon bucket and made fresh saltwater, heated it to 78 degree and left a circulation pump in there as well. Once the live rock was fully "treated" for 5 hours, I carefully took rocks out piece by piece and move it to the fresh saltwater bucket. In this process, I made sure to use the powerhead in the medicated bucket to blow at the rock pieces prior to taking it out and transferring it to the fresh unmedicated bucket.
I left the live rock in the unmedicated bucket of saltwater for 10 minutes prior to putting them back in the display tank.
Impact of Lugol's On Pest and Other Life On Live Rock:
As soon as I put the live rock in the medicated bucket, I noticed several worms flying out of the rock (due to the circulation pump) and squirming around I could not really see any isopods doing this erratic dance from the top down view of my 5 gallon bucket.
After the 5 hour treatment and once the live rock was removed from the medicated bucket, I got a small glass container and poured the sediment at the bottom of the bucket into it to see what had fallen off the live rock. Below is a list of some things I found:
- Copepod (dead)
- Amphipod (dead)
- Bristleworm (dead)
- Hairy Crab (dead)
- Unknown worms (dead)
- Isopod (live)
My Takeaway:
Lugols appears to work in killing a majority of pests, but also kills off your microfauna. I think I can seed my microfauna back using aqua-cultured pods. I also don't think that Lugols makes your live rock "dead" by any means. I will continue my observations over the next 2 weeks to see if a hard cycle is started in my display tank. Use of lugols to rid live rock of Cirolanid Isopods seems only effective to the point that it "stuns" them and forces them off the rock. A higher dosage and a longer treatment time may also impact Cirolanid Isopod death.
One side note is that Cirolanid Isopods may dwell in the sandbed more than live rock. For this reason, I have taken the sand out of my display tank and plan on using new sand after a 2 week observation period to ensure all Cirolanid Isopods are gone. I am also wondering if my encounter of Cirolanid Isopods in every single time live rock was used was in part due to the location of the live rock in the gulf. Could it be that smaller rocks meant for "nano" tanks such as the ones I used the rocks for, come from the lower levels near the sandbed of the ocean where Cirolanid Isopods are more prevalent. This could mean that people who order larger sized rocks or those that are further from the ocean sandbed as less likely to see these pests.
***Disclaimer! this is not a bash on any of the live rock vendors as pests are a given when ordering live rock. The question of this thread is to see possible alternatives to the manual hunting of Cirolanid Isopods and the impact of Lugol's solution on live rock. I am also not a marine biologist, scientist, or even consider myself an "advanced" aquarist. I am simply a regular hobbyist who is extremely tired from hunting for cirolanid isopods past midnight, religiously.
Last edited:
