So, i'm going to try and make the most of this situation and do some testing on these suckers. This is an image I took a few days ago that I had IDed here on the forum. I didn't realize just how big this nudi was until i started finding it's friends; i've never had nudi's before...
Today, i started looking around for more as most folks on the forum were inclined to believe there's no way this fat nudi was flying solo in my system. After manually picking my zoas for about 30 minutes, here are my findings...
So, my initial plan of attack is going to be dipping with coral revive and manual removal. I have also explored options like adding a melanurus wrasse and treating with Flatworm EXIT. I will note that i do have a leopard wrasse and clearly he has absolutely no interest in the nudi's. I am going to treat with flatworm EXIT, but will likely do so in a controlled state (separate tank) out of fear of toxins being released from the nudi's death.
Some things i'd like to prove or disprove...
1.) Flatworm EXIT will kill nudi's under concentrated doses, specifically 4X the recommended dosage
2.) Zoa eating nudi's only eat zoas, not palys
3.) Explore other chemicals resulting in nudi death
4.) Lifespan from both treatment and starvation (how long it takes to nuke them)
5.) What, if any, critters will help fight nudis (currently exploring coral banded shrimp)
My Findings:
1.) Flatworm EXIT will kill nudi's, however there are far better means of controlling them and the required dose is so high it will almost certainly have adverse affects on other inverts. My conclusion; don't waste your time using EXIT for these guys.
2.) While i've had other reefers provide insight that these critters go after both zoas and palys, I never truly experienced this. My case was rare in that these nudi's locked onto a single colony of about a hundred polyps. I did find some on other zoas around this colony, but the nudi's primarily stuck to the same area. I believe this was because food resources were close by so why move around. All of the nudi's I found had yellow coloration; this is the same skirt color of the zoas they were inhabiting & eating.
3.) Ultimately, there are a plethora of ways to kill nudi's. These critters are actually very fragile and believe it or not I often disliked killing them because they are kind of cool... when they're not eating your coral. If you want to see more in depth information on potency and options for dosing please see below. To summarize, there are many ways, and many dips, that will kill the hatched nudi's. The issue is the eggs. I didn't find a single chemical that killed the eggs, not to say there isn't one, but relatively high and low salinity did have an affect on the eggs. I had one suggestion that Interceptor, used on pets for flea treatment, can kill the eggs. However, I was unsuccessful at harvesting any eggs to try.
Although I was able to find and test some eggs, it was short lived. This was a blessing in disguise. While I was bummed that I lost my chance to test the eggs more thoroughly, it further enhanced my belief that salinity is absolutely detrimental to both hatched nudi's and the eggs. Performing an RODI dip killed the grown nudi's within seconds. In addition, the salinity rose in the holding cup I had the eggs in, to 1.030. This also killed the few nudi's I had in the cup, and the eggs that were in there also died. They both basically just melted. So, if you can safely raise your salinity, eventually they'll bite it, but i'm sure this could have negative affects on your system.
Egg Holding Cup:
Egg Holding Cup Salinity Test:
Additionally, manual removal is huge. If you stay on these guys and just keep on removing them, usually at night, you will eventually wipe them out. I'm can not confirm, but it seemed as though the nudi's had to become so large before being able to lay eggs. From my experience, continual removal and scrubbing for any signs of eggs, in addition to RODI dipping my zoas, is what did the nudi's in.
Testing Solutions:
Since so many reefers use Bayer and other dips like Revive, I will highlight those two and say both successfully kill nudi's, but neither is effective for killing eggs. Other solutions like bleach, Ortho bug spray, pure ammonia and bleach were also all effective at killing the nudi's. Unfortunately, most of these would likely not be ideal options for dipping coral. Please dig deeper into the thread if you want more specific testing results.
Bayer Test Results:
Test #1: 2 drops per 1 ounce of tank water
Result #1: no affect
Test #2: 2.5ml of Bayer per 1 ounce of tank water
Result #2: immediate affect, nudi's immobilized, almost entirely unresponsive within 5 minutes, dead within 10 minutes.
4.) I really can't speak to the lifespan of nudi's. My guess is a few weeks from eggs to hatching. As mentioned above, being diligent with your manual removal will make a huge difference in your battle. I was able to grasp where I was at in the life cycle when I was finding both small nudi's, medium ones, and the random large one that would pop up. When finding this wide range in size, I knew there was a plethora of eggs all hatching at different times. Eventually I only found medium to small ones and then just a random medium one, until I didn't find any at all. I'd also mention that a week can go by and you may get excited that you've won the war, then just one day later you'll find one again and you're back to square one.
My suggestion: be diligent! Even when you think these guys are gone, keep inspecting. If the last nudi you pull has laid eggs, it'll be a week or two before you find those new nudis. Keep up with your manual removal.
5.) During my nudi battles, I added a coral banded shrimp and a Mccosker's wrasse. I'm confident in saying that neither did anything in the way of eating these critters. I have no doubt there's something out there that eats these guys, but I was unable do much testing here. Reminder, I also have a leopard wrasse, which also had no interest.
To conclude:
Prevention:
It goes without saying, but QT! I've never had these guys before and figured I always thought I would see the eggs with how meticulous I am... wrong. I introduced eggs into my system and this was the outcome. If you can't QT, I suggest re-gluing your frags to fresh plugs and gently brushing polyps, when plausible, regardless of what you can or can not see.
Final thoughts:
Overall these are cool critters, they're obviously a nuisance, but interesting to say the least. I would not over react if you find them. As long as you are diligent with treatment and stay smart, you can wipe them out fairly easily. At this point, there is no silver bullet. A combination of approaches is your best bet. Do it right and you'll survive!
Today, i started looking around for more as most folks on the forum were inclined to believe there's no way this fat nudi was flying solo in my system. After manually picking my zoas for about 30 minutes, here are my findings...
So, my initial plan of attack is going to be dipping with coral revive and manual removal. I have also explored options like adding a melanurus wrasse and treating with Flatworm EXIT. I will note that i do have a leopard wrasse and clearly he has absolutely no interest in the nudi's. I am going to treat with flatworm EXIT, but will likely do so in a controlled state (separate tank) out of fear of toxins being released from the nudi's death.
Some things i'd like to prove or disprove...
1.) Flatworm EXIT will kill nudi's under concentrated doses, specifically 4X the recommended dosage
2.) Zoa eating nudi's only eat zoas, not palys
3.) Explore other chemicals resulting in nudi death
4.) Lifespan from both treatment and starvation (how long it takes to nuke them)
5.) What, if any, critters will help fight nudis (currently exploring coral banded shrimp)
My Findings:
1.) Flatworm EXIT will kill nudi's, however there are far better means of controlling them and the required dose is so high it will almost certainly have adverse affects on other inverts. My conclusion; don't waste your time using EXIT for these guys.
2.) While i've had other reefers provide insight that these critters go after both zoas and palys, I never truly experienced this. My case was rare in that these nudi's locked onto a single colony of about a hundred polyps. I did find some on other zoas around this colony, but the nudi's primarily stuck to the same area. I believe this was because food resources were close by so why move around. All of the nudi's I found had yellow coloration; this is the same skirt color of the zoas they were inhabiting & eating.
3.) Ultimately, there are a plethora of ways to kill nudi's. These critters are actually very fragile and believe it or not I often disliked killing them because they are kind of cool... when they're not eating your coral. If you want to see more in depth information on potency and options for dosing please see below. To summarize, there are many ways, and many dips, that will kill the hatched nudi's. The issue is the eggs. I didn't find a single chemical that killed the eggs, not to say there isn't one, but relatively high and low salinity did have an affect on the eggs. I had one suggestion that Interceptor, used on pets for flea treatment, can kill the eggs. However, I was unsuccessful at harvesting any eggs to try.
Although I was able to find and test some eggs, it was short lived. This was a blessing in disguise. While I was bummed that I lost my chance to test the eggs more thoroughly, it further enhanced my belief that salinity is absolutely detrimental to both hatched nudi's and the eggs. Performing an RODI dip killed the grown nudi's within seconds. In addition, the salinity rose in the holding cup I had the eggs in, to 1.030. This also killed the few nudi's I had in the cup, and the eggs that were in there also died. They both basically just melted. So, if you can safely raise your salinity, eventually they'll bite it, but i'm sure this could have negative affects on your system.
Egg Holding Cup:
Egg Holding Cup Salinity Test:
Additionally, manual removal is huge. If you stay on these guys and just keep on removing them, usually at night, you will eventually wipe them out. I'm can not confirm, but it seemed as though the nudi's had to become so large before being able to lay eggs. From my experience, continual removal and scrubbing for any signs of eggs, in addition to RODI dipping my zoas, is what did the nudi's in.
Testing Solutions:
Since so many reefers use Bayer and other dips like Revive, I will highlight those two and say both successfully kill nudi's, but neither is effective for killing eggs. Other solutions like bleach, Ortho bug spray, pure ammonia and bleach were also all effective at killing the nudi's. Unfortunately, most of these would likely not be ideal options for dipping coral. Please dig deeper into the thread if you want more specific testing results.
Bayer Test Results:
Test #1: 2 drops per 1 ounce of tank water
Result #1: no affect
Test #2: 2.5ml of Bayer per 1 ounce of tank water
Result #2: immediate affect, nudi's immobilized, almost entirely unresponsive within 5 minutes, dead within 10 minutes.
4.) I really can't speak to the lifespan of nudi's. My guess is a few weeks from eggs to hatching. As mentioned above, being diligent with your manual removal will make a huge difference in your battle. I was able to grasp where I was at in the life cycle when I was finding both small nudi's, medium ones, and the random large one that would pop up. When finding this wide range in size, I knew there was a plethora of eggs all hatching at different times. Eventually I only found medium to small ones and then just a random medium one, until I didn't find any at all. I'd also mention that a week can go by and you may get excited that you've won the war, then just one day later you'll find one again and you're back to square one.
My suggestion: be diligent! Even when you think these guys are gone, keep inspecting. If the last nudi you pull has laid eggs, it'll be a week or two before you find those new nudis. Keep up with your manual removal.
5.) During my nudi battles, I added a coral banded shrimp and a Mccosker's wrasse. I'm confident in saying that neither did anything in the way of eating these critters. I have no doubt there's something out there that eats these guys, but I was unable do much testing here. Reminder, I also have a leopard wrasse, which also had no interest.
To conclude:
- Manual removal is easily the most important key to beating zoa eating nudis
- Fresh water dipping zoa colonies and frags is beneficial in combating both grown nudi's and eggs. This is not to say it will destroy the eggs in the duration of your dip, but it definitely has a positive impact on killing them over time. In addition, raising your salinity will also have a positive impact. 1.030 salinity killed both grown nudi's and eggs after 10 days of exposure.
- Dips like Bayer and Revive will kill the grown nudi's, but are essentially worthless for treating eggs. If you're going to dip with these solutions to kill the grown nudi's, you should also inspect and scrub diligently for eggs and consider an RODI dip.
- While there may be critters out there that eat nudi's, I was unable to findd one. Tangs, rabbitfish, gobies, clowns, mccosker's and leopard wrasses as well as coral banded shrimp or hermits were not effective.
- Nudi's are resilient and they lay a lot of eggs. We all know how hard it is to catch a fish in our reef. Imagine trying to find eggs in the same environment. While you may have checked and come up nudi free for several days or even a week, keep looking. Chances are you missed eggs somewhere and those nudi's are bound to show up. Maintain a daily regiment for egg and nudi inspection and remove them accordingly.
Prevention:
It goes without saying, but QT! I've never had these guys before and figured I always thought I would see the eggs with how meticulous I am... wrong. I introduced eggs into my system and this was the outcome. If you can't QT, I suggest re-gluing your frags to fresh plugs and gently brushing polyps, when plausible, regardless of what you can or can not see.
Final thoughts:
Overall these are cool critters, they're obviously a nuisance, but interesting to say the least. I would not over react if you find them. As long as you are diligent with treatment and stay smart, you can wipe them out fairly easily. At this point, there is no silver bullet. A combination of approaches is your best bet. Do it right and you'll survive!
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, and you can see many nudi bodies.
