Use chloroquine phosphate for fish quarantine.

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I tried using chloroquine phosphate to quarantine 100 juvenile Red Emperor Snapper (Lutjanus erythopterus). On the first day, I added 15 ppm. Since the drug degrades over time, I then added 2 ppm every other day, for a total of three supplementary doses. Before the third top‑up, the animals were doing very well and feeding vigorously. However, after the third addition, acute mass mortality began to occur. At the same time, water quality started to deteriorate, with ammonia‑nitrogen rising to 0.25–0.30 ppm. I put a small amount of activated carbon into the tank to adsorb the drug, and then added six porcupinefish, one moorish idol, and one clownfish to the system. The next day, five of the porcupinefish died, while the moorish idol appeared unaffected. Water quality did not improve, and I suspect that both the juvenile snappers and the porcupinefish do not tolerate high concentrations of chloroquine phosphate well.
 

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I use chloroquine as well for the majority of my Qts. I don't redose it every few days as some do. I dose 40mg/gallon once and leave it at that level for 21 days. If I need to do a water change I only replace the chloroquine I removed in the water change. Sounds like you overdosed the medicine.
 

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For CP, I recommend 35 mg per gallon and allow to work for two weeks with air stone added. Tank may have gotten too much added allowing an increase in ammonia and oxygen levels to decrease
Sorry to hear about the significant loss
 
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I use chloroquine as well for the majority of my Qts. I don't redose it every few days as some do. I dose 40mg/gallon once and leave it at that level for 21 days. If I need to do a water change I only replace the chloroquine I removed in the water change. Sounds like you overdosed the medicine.
I have experienced white spot disease when quarantining foxface fish at a concentration of 10 mg/L. Therefore, I think that a concentration of 10 mg/L may not be sufficient to prevent this type of disease.
 
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For CP, I recommend 35 mg per gallon and allow to work for two weeks with air stone added. Tank may have gotten too much added allowing an increase in ammonia and oxygen levels to decrease
Sorry to hear about the significant loss
No, I have measured the dissolved oxygen level, and it was between 5.5 and 6 mg/L. I agree that the medication at high concentrations may have had a negative impact on the nitrification system. However, I do not think that 10 ppm of chloroquine phosphate is sufficient to prevent ich
 

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No, I have measured the dissolved oxygen level, and it was between 5.5 and 6 mg/L. I agree that the medication at high concentrations may have had a negative impact on the nitrification system. However, I do not think that 10 ppm of chloroquine phosphate is sufficient to prevent ich
It takes several days for CP to take effect and you can add if amount not sufficient but I would not add at rate of every other day
 

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I tried using chloroquine phosphate to quarantine 100 juvenile Red Emperor Snapper (Lutjanus erythopterus). On the first day, I added 15 ppm. Since the drug degrades over time, I then added 2 ppm every other day, for a total of three supplementary doses. Before the third top‑up, the animals were doing very well and feeding vigorously. However, after the third addition, acute mass mortality began to occur. At the same time, water quality started to deteriorate, with ammonia‑nitrogen rising to 0.25–0.30 ppm. I put a small amount of activated carbon into the tank to adsorb the drug, and then added six porcupinefish, one moorish idol, and one clownfish to the system. The next day, five of the porcupinefish died, while the moorish idol appeared unaffected. Water quality did not improve, and I suspect that both the juvenile snappers and the porcupinefish do not tolerate high concentrations of chloroquine phosphate well.

I think your dose ended up higher than anticipated, chloroquine breaks down fairly slowly. I’m also not convinced that carbon removes it.

Here is my article on chloroquine. I don’t recommend it much anymore due to ammonia spikes and odd mortality events.

 
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I think your dose ended up higher than anticipated, chloroquine breaks down fairly slowly. I’m also not convinced that carbon removes it.

Here is my article on chloroquine. I don’t recommend it much anymore due to ammonia spikes and odd mortality events.

I forgot where I saw that the therapeutic dose of chloroquine phosphate is 10–20 ppm. During quarantine, I used a dose of 10 ppm, but the fish still broke out with ich, so I chose a starting dose of 15 ppm. Even if you add up all the doses over the entire course of treatment, the total is only 21 ppm. The reason I use chloroquine phosphate is that in China, the treatment cost with chloroquine phosphate is lower than with copper, and the sand in my filter media is full of coral gravel, which makes the copper demand spike dramatically. It looks like I need to find a way to measure chloroquine phosphate in the water. I remember you mentioned before using a UV spectrophotometer to test it.
 
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It takes several days for CP to take effect and you can add if amount not sufficient but I would not add at rate of every other day
For now, using copper seems safer and more reliable because the drug concentration can be monitored. I often worry that the chloroquine level in my tank has dropped below the therapeutic concentration.
 

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For now, using copper seems safer and more reliable because the drug concentration can be monitored. I often worry that the chloroquine level in my tank has dropped below the therapeutic concentration.
Coppersafe or copper power at 2.25ppm best
 

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I forgot where I saw that the therapeutic dose of chloroquine phosphate is 10–20 ppm. During quarantine, I used a dose of 10 ppm, but the fish still broke out with ich, so I chose a starting dose of 15 ppm. Even if you add up all the doses over the entire course of treatment, the total is only 21 ppm. The reason I use chloroquine phosphate is that in China, the treatment cost with chloroquine phosphate is lower than with copper, and the sand in my filter media is full of coral gravel, which makes the copper demand spike dramatically. It looks like I need to find a way to measure chloroquine phosphate in the water. I remember you mentioned before using a UV spectrophotometer to test it.

That’s the problem with chloroquine - fish toxicity shows up around 20 ppm, but 15 ppm doesn’t always control active ich infections.
 
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Coppersafe or copper power at 2.25ppm best
Both of these products are very expensive in China—of course, I mean relative to local incomes. I would probably lean toward using Cupramine for larger-volume aquariums and Copper Power for smaller-volume ones.
 
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That’s the problem with chloroquine - fish toxicity shows up around 20 ppm, but 15 ppm doesn’t always control active ich infections.
Recently, I came across a new fish medication at a fish store—it's from the Waterlife brand and is claimed to treat ich and Benedenia. Are you familiar with it?
1782198496853.png
 

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Recently, I came across a new fish medication at a fish store—it's from the Waterlife brand and is claimed to treat ich and Benedenia. Are you familiar with it?
1782198496853.png
Waterlife makes good products but my concern would be a medication that treats flukes and ich at same time. If using cupramine, start out at .45ppm although copper power is a safer form of treatment
 

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Recently, I came across a new fish medication at a fish store—it's from the Waterlife brand and is claimed to treat ich and Benedenia. Are you familiar with it?
1782198496853.png

I’ve not used it, but I’m familiar with its components; copper, malachite green and formalin. I’ve never heard of all three being used together. Do the instructions include testing for copper? If not, don’t use it as there is no way to dose copper without testing for the amount of it in the water.
 
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I’ve not used it, but I’m familiar with its components; copper, malachite green and formalin. I’ve never heard of all three being used together. Do the instructions include testing for copper? If not, don’t use it as there is no way to dose copper without testing for the amount of it in the water.
No, the product does not include any description of its ingredients; it only states that it should not be used on cartilaginous fish, invertebrates, or aquatic plants. I also could not find any description of the product's ingredients on its official website—only the instructions for use.
1782266032949.png
 

Jay Hemdal

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No, the product does not include any description of its ingredients; it only states that it should not be used on cartilaginous fish, invertebrates, or aquatic plants. I also could not find any description of the product's ingredients on its official website—only the instructions for use.
1782266032949.png

Here is what I found:

Waterlife Cuprazin is a copper-based medication. The primary active ingredient is copper sulfate, which is often formulated as a chelated copper. Depending on the specific batch and formulation, it also includes co-active ingredients like malachite green and formaldehyde.

I also found that comment that the formulation can change very odd...not sure what that means.

You cannot safely dose any copper product without knowing the appropriate concentration, and then test for that. None of the ingredients can treat Neobenedenia at doses that won't kill the fish. Formalin can be used as a high dose dip, but you need to change the water afterwards, and this product obviously doesn't have enough formalin in it for that.
 
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Here is what I found:

Waterlife Cuprazin is a copper-based medication. The primary active ingredient is copper sulfate, which is often formulated as a chelated copper. Depending on the specific batch and formulation, it also includes co-active ingredients like malachite green and formaldehyde.

I also found that comment that the formulation can change very odd...not sure what that means.

You cannot safely dose any copper product without knowing the appropriate concentration, and then test for that. None of the ingredients can treat Neobenedenia at doses that won't kill the fish. Formalin can be used as a high dose dip, but you need to change the water afterwards, and this product obviously doesn't have enough formalin in it for that.
Thank you very much. Also, I am curious: in public aquariums in Europe and the United States, when conducting fish quarantine, do they use copper sulfate more often, or other copper-based products? Or do they use chloroquine phosphate?
 
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To investigate whether the fish deaths were caused by the drug or if there was another underlying reason, I decided to purchase three juvenile Red Emperor Snapper (Lutjanus erythopterus) for an experiment. This species is currently relatively well-established in captive breeding, making it quite easy to obtain. I planned to eliminate the negative effects of elevated ammonia nitrogen in the water by adding an ammonia binder, and on the day after arrival, I directly added 20 ppm of chloroquine phosphate. During the experiment, I avoided water changes as much as possible; when a water change became necessary, I replenished the chloroquine phosphate in the replacement water.
 

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Thank you very much. Also, I am curious: in public aquariums in Europe and the United States, when conducting fish quarantine, do they use copper sulfate more often, or other copper-based products? Or do they use chloroquine phosphate?

That's a good question - I don't know. Chloroquine is less often used than copper, but many public aquariums still rely on ionic copper, and that is more stressful than the amine-chelated copper products like coppersafe or copper power. Because of the large water volumes involved, those products can end up being very expensive.

Many aquarium run hyposalinity for ich and Neobenedenia flukes.....
 

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