Parasite problem on Blenny?

think2100

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Can anybody tell me if this Canary Blenny looks healthy or excessively thin? I have had him for a couple weeks and he seems to be getting plenty of food, but still looks thin to me. I have seen what looks like scratching on the sand a couple of times so now I’m worried about parasites. Should I try to

get him out of the tank?
 

vetteguy53081

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Can anybody tell me if this Canary Blenny looks healthy or excessively thin? I have had him for a couple weeks and he seems to be getting plenty of food, but still looks thin to me. I have seen what looks like scratching on the sand a couple of times so now I’m worried about parasites. Should I try to

get him out of the tank?
Video is blurry to see anything on body and is thin and often a subject of edema where it feeds off its liver. Please provide clearer video
 

Jay Hemdal

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Can anybody tell me if this Canary Blenny looks healthy or excessively thin? I have had him for a couple weeks and he seems to be getting plenty of food, but still looks thin to me. I have seen what looks like scratching on the sand a couple of times so now I’m worried about parasites. Should I try to

get him out of the tank?

Yes, it does look thin. We see this a lot in blennies. I even started a sticky thread about it:

 
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think2100

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Can anybody tell me if this Canary Blenny looks healthy or excessively thin? I have had him for a couple weeks and he seems to be getting plenty of food, but still looks thin to me. I have seen what looks like scratching on the sand a couple of times so now I’m worried about parasites. Should I try to

get him out of the tank?
Video is blurry to see anything on body and is thin and often a subject of edema where it feeds off its liver. Please provide clearer video
Not easy to do as he’s constantly in and out of focus. I’ve added some photos to help.
20260516_165912_FF8568CB-F275-4EF5-88A4-E1EA41FAAC51.png


20260516_165912_2489FCE8-FAC0-409C-A041-B9E2D7B392CC.png


20260516_165912_522D5586-EDCE-485A-9DF4-9957AC710F5C.png


20260516_165912_E7708E14-9E83-41E9-83A7-579C3DE9679D.png


20260516_165912_0FE2CBBC-85DA-4D18-84B4-00345FD5E019.png


20260516_165912_07925997-EAB4-4752-98EC-34A239B482A1.png


20260516_165912_2F917155-9FAA-4FC3-B345-94DA854AB84E.png


20260516_165912_CDE41DB1-3688-4194-A77E-16BB4AC19349.png
 
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think2100

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Can anybody tell me if this Canary Blenny looks healthy or excessively thin? I have had him for a couple weeks and he seems to be getting plenty of food, but still looks thin to me. I have seen what looks like scratching on the sand a couple of times so now I’m worried about parasites. Should I try to

get him out of the tank?

Yes, it does look thin. We see this a lot in blennies. I even started a sticky thread about it:

Is this likely just not enough food? The occasional scratching on sand made me think parasites but I do not see any marks on the body?
 
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think2100

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Can anybody tell me if this Canary Blenny looks healthy or excessively thin? I have had him for a couple weeks and he seems to be getting plenty of food, but still looks thin to me. I have seen what looks like scratching on the sand a couple of times so now I’m worried about parasites. Should I try to

get him out of the tank?

Yes, it does look thin. We see this a lot in blennies. I even started a sticky thread about it:

Read the thread. Very helpful! I wondered if the problem was just the frenetic calorie expenditure, and I’ve begun some extra target feeding, but the scratching worries me. If it is a parasite will they spread to other fish?
 

vetteguy53081

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Not easy to do as he’s constantly in and out of focus. I’ve added some photos to help.
20260516_165912_FF8568CB-F275-4EF5-88A4-E1EA41FAAC51.png


20260516_165912_2489FCE8-FAC0-409C-A041-B9E2D7B392CC.png


20260516_165912_522D5586-EDCE-485A-9DF4-9957AC710F5C.png


20260516_165912_E7708E14-9E83-41E9-83A7-579C3DE9679D.png


20260516_165912_0FE2CBBC-85DA-4D18-84B4-00345FD5E019.png


20260516_165912_07925997-EAB4-4752-98EC-34A239B482A1.png


20260516_165912_2F917155-9FAA-4FC3-B345-94DA854AB84E.png


20260516_165912_CDE41DB1-3688-4194-A77E-16BB4AC19349.png
With the low lighting, as of now dont see evidence of ich
 

Jay Hemdal

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Read the thread. Very helpful! I wondered if the problem was just the frenetic calorie expenditure, and I’ve begun some extra target feeding, but the scratching worries me. If it is a parasite will they spread to other fish?

Parasites, both internal and external, take food energy away from the fish. That parasite is evolved to kill its host because then it dies as well. In captivity, things get worse and the fish often die.

Given the scratching, I’d consider dosing the tank with praziquantel. It’s reef safe. It kills external flukes and internal tapeworms. Those aren’t all the possible parasites, but it’s a good start.

Here is a post about dosing with prazi:
 
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think2100

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Read the thread. Very helpful! I wondered if the problem was just the frenetic calorie expenditure, and I’ve begun some extra target feeding, but the scratching worries me. If it is a parasite will they spread to other fish?

Parasites, both internal and external, take food energy away from the fish. That parasite is evolved to kill its host because then it dies as well. In captivity, things get worse and the fish often die.

Given the scratching, I’d consider dosing the tank with praziquantel. It’s reef safe. It kills external flukes and internal tapeworms. Those aren’t all the possible parasites, but it’s a good start.

Here is a post about dosing with prazi:
So received this fish from Dr. Reef a couple of weeks ago, as with all the fish in my tank. They all went through the following process:

“Fish go straight into quarantine tanks with either Chloroquine Phosphate or Copper power.
Starting doses are: CP at 20 mg/gal and Copper at 1ppm
After 24 hrs, we increase the doses to their final levels, CP at 40 mg/gal or Copper at 2.25-2.50 ppm
Fish stay in these levels for 2 weeks.
After 14 days we move them to observation tanks.
In observation, We administer Prazipro and Metro to get rid of internal parasites. We repeat treatment every 3 to 5 days.
Meanwhile we feed Fish Bendazole along with Metronidazole, mixed in food to rid Uronema and internal parasites.
At 4-6 weeks fish are ready to ship. If customers likes us to keep them in observation little longer, we can, please let us know.
Feeding: We feed 2 times a day. All fish are fed a 50/50 mixture of frozen mysis & brine. In some cases, we also feed frozen bloodworms.”

Given that, is it pointless for me to dose my tank with Prazipro?
 

Jay Hemdal

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So received this fish from Dr. Reef a couple of weeks ago, as with all the fish in my tank. They all went through the following process:

“Fish go straight into quarantine tanks with either Chloroquine Phosphate or Copper power.
Starting doses are: CP at 20 mg/gal and Copper at 1ppm
After 24 hrs, we increase the doses to their final levels, CP at 40 mg/gal or Copper at 2.25-2.50 ppm
Fish stay in these levels for 2 weeks.
After 14 days we move them to observation tanks.
In observation, We administer Prazipro and Metro to get rid of internal parasites. We repeat treatment every 3 to 5 days.
Meanwhile we feed Fish Bendazole along with Metronidazole, mixed in food to rid Uronema and internal parasites.
At 4-6 weeks fish are ready to ship. If customers likes us to keep them in observation little longer, we can, please let us know.
Feeding: We feed 2 times a day. All fish are fed a 50/50 mixture of frozen mysis & brine. In some cases, we also feed frozen bloodworms.”

Given that, is it pointless for me to dose my tank with Prazipro?

The prazipro that the fish was given would help with tapeworms. Pretty often, prazi treatments are not 100% effective against external flukes (which could be why your fish is still scratching). I'm not sure what they mean by "bendazole". That could be Fenbendazole, which treats for nematode worms. It could also mean albendazole, but I've not used that before.

I would increase the feeding amount an frequency. Trying prazi again might show if there are still external flukes present on the fish. Tapeworms are a "one and done" treatment, fish don't get reinfected with those in aquariums because these have a secondary host that isn't present in aquariums.
 
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think2100

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The prazipro that the fish was given would help with tapeworms. Pretty often, prazi treatments are not 100% effective against external flukes (which could be why your fish is still scratching). I'm not sure what they mean by "bendazole". That could be Fenbendazole, which treats for nematode worms. It could also mean albendazole, but I've not used that before.

I would increase the feeding amount an frequency. Trying prazi again might show if there are still external flukes present on the fish. Tapeworms are a "one and done" treatment, fish don't get reinfected with those in aquariums because these have a secondary host that isn't present in aquariums.
Thanks Jay. I’ll give the Prazipro a try. I have upped the feeding to 4 times a day, targeting the blenny (he’s a little slow compared to some of the other fish). However, it is a young tank, and as I bump food up, ammonia rises as well. Starting 25% 24 hour slow AWC to dilute ammonia.
 

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Thanks Jay. I’ll give the Prazipro a try. I have upped the feeding to 4 times a day, targeting the blenny (he’s a little slow compared to some of the other fish). However, it is a young tank, and as I bump food up, ammonia rises as well. Starting 25% 24 hour slow AWC to dilute ammonia.

Try to keep the ammonia at or below 0.25 ppm, and for sure below 0.50 ppm. However, some ammonia tests just aren’t up to the task (API is tough to read).
 
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think2100

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Thanks Jay. I’ll give the Prazipro a try. I have upped the feeding to 4 times a day, targeting the blenny (he’s a little slow compared to some of the other fish). However, it is a young tank, and as I bump food up, ammonia rises as well. Starting 25% 24 hour slow AWC to dilute ammonia.

Try to keep the ammonia at or below 0.25 ppm, and for sure below 0.50 ppm. However, some ammonia tests just aren’t up to the task (API is tough to read).
At .14 now according to Hannah so fish are not stressed, and I expect that to drop with the awc.
 

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