Feeding Metronidazole to fish in reef

[ss88]

Anyone here ever use Metronidazole to feed fish in a reef tank?
Noga has different treatment protocols ranging from 25mg/kg to 100mg/kg.
If you did use it in a reef tank, did you also run ROX carbon during the treatment.

I have a situation involving a Halichoeres chloropterus. The specimen was added to the aquarium over 3 years ago. The last addition to the system was over 1 year ago and included a Coris gaimard. The C. gaimard perished last month and never really gained weight, necropsy was inconclusive beside mechanical damage from power head. This was the only fish lost in the system within the last year. Dissection of the intestine showed nothing irregular. Over the last two months I have noticed that the H. chloropterus has been losing weight. I have tried treating with oral praziquantel. Surely its overdosed given the complexity of feeding a community tank, but no ill effects have been noted. That said, I have concluded day 6. (50mg/kg every other day) of the treatment and his condition continues to decline. None of the other 30+ fish in the system show any symptoms. I would like to attempt to treat with Metronidazole but am hesitant given the system is a full sps reef.

I have seen other aquarist use Metronidazole feed in reefs. But how safe is it?

 

[ss88]

Also to note, all fish in this system went through a 90 day quarantine process involving copper and praziquantel bath. No oral medications given during quarantine process.

 

[vetteguy53081]

Anyone here ever use Metronidazole to feed fish in a reef tank?
Noga has different treatment protocols ranging from 25mg/kg to 100mg/kg.
If you did use it in a reef tank, did you also run ROX carbon during the treatment.

I have a situation involving a Halichoeres chloropterus. The specimen was added to the aquarium over 3 years ago. The last addition to the system was over 1 year ago and included a Coris gaimard. The C. gaimard perished last month and never really gained weight, necropsy was inconclusive beside mechanical damage from power head. This was the only fish lost in the system within the last year. Dissection of the intestine showed nothing irregular. Over the last two months I have noticed that the H. chloropterus has been losing weight. I have tried treating with oral praziquantel. Surely its overdosed given the complexity of feeding a community tank, but no ill effects have been noted. That said, I have concluded day 6. (50mg/kg every other day) of the treatment and his condition continues to decline. None of the other 30+ fish in the system show any symptoms. I would like to attempt to treat with Metronidazole but am hesitant given the system is a full sps reef.

I have seen other aquarist use Metronidazole feed in reefs. But how safe is it?

I dont recommend it. While it helps with protozoan and bacterial issues, it must be Precise when used and should be used when absolutely necessary

 

[ss88]

I guess I’m less concerned about the potential for overdosing. The medication seems to have a fairly wide dosage range 25 to 100mg per kg. Although the treatment duration is different for those dosage ranges. The half-life of the medication is rather short. I think 8 hrs if not mistaken in humans. Also I recall reading somewhere that the digestive uptake is limited.

I am however, worried about killing some of my corals.

 

[PharmrJohn]

I guess I’m less concerned about the potential for overdosing. The medication seems to have a fairly wide dosage range 25 to 100mg per kg. Although the treatment duration is different for those dosage ranges. The half-life of the medication is rather short. I think 8 hrs if not mistaken in humans. Also I recall reading somewhere that the digestive uptake is limited.

I am however, worried about killing some of my corals.

You are correct on the half-life. Remember that it takes 5 half-lives to exit a system (a human anyway) and be non-therapeutic. Ten half-lives to leave no trace.

 

[MnFish1]

"The medication seems to have a fairly wide dosage range 25 to 100mg per kg. Although the treatment duration is different for those dosage ranges. "

You should be concerned about overdosing. First the half-life in fish is not the same as the 1/2 life in humans. second the sentence does not imply that its safe to dose metronidazole in a wide range. -the key is the higher doses are used only for shorter times.

 

[ss88]

You should be concerned about overdosing. First the half-life in fish is not the same as the 1/2 life in humans. second the sentence does not imply that its safe to dose metronidazole in a wide range. -the key is the higher doses are used only for shorter times.

True.

 

[Jay Hemdal Verified Community Expert]

Also to note, all fish in this system went through a 90 day quarantine process involving copper and praziquantel bath. No oral medications given during quarantine process.

Metronidazole is effective at reducing loading from flagellates such as Hexamita and Spironucleaus. These are normal gut flora, but sometimes grow in numbers and cause the fish issues. There are other reasons for chronic wasting in fish though - often Mycobacteria which is not treatable.

Metro is one of the few drugs that can be dosed as a percentage in the food and not mg per kg of fish weight.

The usual dose for metro is 1 to 2% by weight of food, bound with Focus or some other binder. However, it is very bitter and many fish refuse to eat it at higher doses.

Have you seen my medicated food article?

Proper Dosing of Medicated Foods

Proper Dosing of Medicated Foods Jay Hemdal c. 2020 Oral medications are an excellent way to target internal diseases of fishes. Marine fish absorb aquarium water, so in certain cases, they “drink” enough medication from the water to effect a cure. However, freshwater fish actively export...

www.reef2reef.com

 

[ss88]

The usual dose for metro is 1 to 2% by weight of food, bound with Focus or some other binder. However, it is very bitter and many fish refuse to eat it at higher doses.

Generally my fish are wise to my attempts to feed any type of medicated foods. I normally end up using mostly nori soaked in gelatin as it seems to mask the flavor best.

There are other reasons for chronic wasting in fish though - often Mycobacteria which is not treatable.

Yes I read about this in one of your earlier post. Aquarium Fish: The ‘Eyes’ Have it
Relatively new fish, perhaps 5 years total in captivity.

@Jay Hemdal have you ever used food soaked Metronidazole in a reef tank? Some basic math shows this being a concentration many times lower than normal water immersion therapy. Like 1% assuming zero food was consumed and everything disbursed into water column.

I do have some sacrificial Acro frags I will likely test for 24hrs to see if any ill effects are noted in a control setting.

 

[Jay Hemdal Verified Community Expert]

Generally my fish are wise to my attempts to feed any type of medicated foods. I normally end up using mostly nori soaked in gelatin as it seems to mask the flavor best.

Yes I read about this in one of your earlier post. Aquarium Fish: The ‘Eyes’ Have it
Relatively new fish, perhaps 5 years total in captivity.

@Jay Hemdal have you ever used food soaked Metronidazole in a reef tank? Some basic math shows this being a concentration many times lower than normal water immersion therapy. Like 1% assuming zero food was consumed and everything disbursed into water column.

I do have some sacrificial Acro frags I will likely test for 24hrs to see if any ill effects are noted in a control setting.

I’ve dosed related dimetronidazole in food with no issues.

You’re correct, the 1% in food fed at the typical 3% by body weight ends up being of no consequence to corals.