Most of our marine fishes come from the wild. It isn’t unusual for the fish to be carrying a worm, bacterial, or parasitic infection in its intestinal track. It’s been estimated that up to 30% of the fishes in the wild have some kind of intestinal infection. This number can considerably increase as fish are kept in holding tanks along transfer points, where they can share diseases and infections.
These pathogens are siphoning nutrition away from the fish. In the wild, this is not much of an issue. The fish can find enough nutrition for its own needs and the needs of the infections. If the intake of nutrients is enough -- the fish is satisfied; the pathogens are satisfied. However, I the aquarist, am not satisfied. I want the parasites out.
Diagnosis can be problematic. The best thing is to know what normal fecal matter looks like. Normal fecal matter comes out the vent (anal opening) almost sandy -- not formed at all. It is likened to a 'spray of bits.'
Back to the parasites:
Most of these parasites and pathogens are types of worms. So in the following text I refer to ‘worms’ but mean this whole group of intestinal disorders caused by worms, other parasites, and some bacteria. Thus, I’ve used the word de-worming to describe the curing of marine fish of these invaders.
If the fishes are de-wormed (which is very easy to do) the aquarist does not have to worry about the worms taking nutrients away from their fishes.
Unfortunately, it isn't easy to always tell if a fish has these worms. The symptoms of a worm infestation match other intestinal disorders. Generally though, the symptoms and observations of fishes with intestinal worms include:
Strange feces (stringy, solid lengths, colored wrong, worms in feces, etc.)
Appearance of worms at vent (anal opening)
Fish eats voraciously (the proper foods) but doesn’t seem to gain weight
Fish eats but is losing weight, or seems to be wasting away
Fish eats but is losing coloration and clear marking boundaries
Fish eating habits have changed to picking at foods or it stops eating
Unfortunately, if allowed to go uncorrected, the fish could just stop eating or never start to eat when it gets to the hobbyist.
Obviously the above set of symptoms can apply to certain other conditions, however, the strange feces is the one symptom you'll come to rely upon most, for this diagnosis. You have to be a Super Pooper Snooper to sniff out the problem.
I would like to cover in this post the three most common problems which are indicated by the above symptoms.
There are three (3) basic possibilities when it comes to an intestinal problem. I'm getting only a little bit more technical here. The three groups or culprits for intestinal disorders are:
Bacteria
Parasitic Worms
Dinoflagellates
Each has a 'favorite' remedy or medication. For the inexperienced hobbyist, separating the three may be difficult. However, the majority of the time, when the fecal matter is evident of an intestinal organism, it is a parasitic worm of some kind.
Garlic is not a remedy. It has been suspected of helping in one case of internal parasites, but hasn't been found to be reproducible. The fish was fed solid chunks of it. Garlic juice does nothing in this case.
Knowing how long you have had this fish would help in determining which of the three is the culprit. If you kept the fish in quarantine when it was acquired, this will help in trying to separate which of the culprits is at work. Since I don't know this information when I wrote this post, I have to assume either possibility and provide how to deal with each.
Whatever the intestinal problem, the fish needs the best water quality and the best diet AND supplements added to its diet. Remember, it is eating for two or two thousand!
If the fish is not eating then the only way to get medication to the intestinal track is to put the fish in a quarantine tank and treat the water with chemicals that will kill the internal condition. The drug Praziquantel (a.k.a. Droncit) will treat intestinal worms (see below for other suggestions), Maracyn Two for Saltwater fish will treat an internal bacterial infection and Metronizazole will treat dinoflagellate infections.
To be conservative: I recommend either of two ways forward:
1. If you've had your fish for several months or more: First check your source water for contaminants. Use only the best source water and make up a new batch of salt water. Now check that freshly made up water for quality/contaminants. If it passes, then adjust it for pH, temperature and salinity, mix some more, then do an 80% water change and see if the fish seems to 'perk up' (e.g., starts eating or eats more or swims around more in the open). If the fish definitely perks up then it maybe a combo of water conditions and bacteria. In this case, I'd treat the fish for an internal bacterial infection. Move fish to a hospital/quarantine tank and treat with Maracyn Two for Saltwater fishes. Begin with a double dose and continue double dosing what is recommended on the medicine insert. With proper nutrition and water quality, the fish may gain control and conquer the internal infection.
2. If you recently acquired the fish: Treat the fish for worms (using Praziquantel or an alternate noted below) first and if no improvement, treat for dinoflagellates (using a medication containing Metronizazole). You can use a medication that includes both these (see below).
If the fish was fat and eating properly and being fed a proper diet, including vitamin and fat supplements, then the fish can live without eating for several weeks, providing all other environmental and water quality conditions are as they should be and the fish is not otherwise diseased. Praziquantel is best administered orally so if your fish isn't eating, try to get the fish eating.
De-worm all newly acquired fishes with Praziquantel (or one of the given alternative drugs given below) right after acclimation and as soon as the fish begins to eat.
Dose Praziquantel (or an alternate drug) as instructed below. Wait 6 days and dose again. This treatment is over!
----------
Medications:
Maracyn Two for Saltwater fishes. Made by Mardel. Contains the antibiotic Minocycline with B complex vitamins (to stimulate appetite). Available at some LFSs, Petco, and on line.
------------------
Praziquantel. Praziquantel may be hard to find. But it is available on-line along with other medications at: National Fish Pharmaceuticals, FISH DISEASE . . It is also available on-line from PondRX PondRX - Home. . Unfortunately, the quantity of Praziquantel you need to order as a minimum order may be more than you'll need in the next few years. Search for more places though for smaller quantities or split the smallest container with other hobbyists/club members.
USE OF PRAZIQUANTEL: It is administered at 23mg per pound of fish, in their normal food. Wait 6 days, then treat again. Verify the 'cure' by observing the faces form/shape. There is no need to move the fish to a quarantine/hospital tank. The fish can be treated wherever it is, so long as you are putting the medication into the food.
There is a commercially prepared anti-parasitic pellet food available. It is made by Jungle. The product name is: Anti-Parasite Medicated Fish Food. The active ingredients in this food are levamisole (also a stimulant for the fish immune system), Metrodinazole, and Praziquantel. This particular formula will kill a much broader spectrum of intestinal organisms. Follow package directions or add some to food.
The aquarist is looking for a treatment that the fish will swallow (not a water treatment). However, if the fish isn't eating, the water treatment is necessary. Follow directions that comes with these alternate medications.
Alternative Meds (overseas). I try to be on the look-out for meds available outside North America. I've recently come across some that are suitable for de-worming. Those aquarists in the UK and Europe may find Fenbendazole or Piperazine more readily available. They are dosed at 250mg/100g of food, fed for 7 to 10 days. Medications containing these will likely come with dosing instructions. Follow label instructions for administering these products.
-----------------
Metronizazole. Also found in several products. (See above). Follow the directions that come with the medication.
BE A SUPER POOPER SNOOPER. Watch your fishes' feces! (This is a hobby? )
These pathogens are siphoning nutrition away from the fish. In the wild, this is not much of an issue. The fish can find enough nutrition for its own needs and the needs of the infections. If the intake of nutrients is enough -- the fish is satisfied; the pathogens are satisfied. However, I the aquarist, am not satisfied. I want the parasites out.
Diagnosis can be problematic. The best thing is to know what normal fecal matter looks like. Normal fecal matter comes out the vent (anal opening) almost sandy -- not formed at all. It is likened to a 'spray of bits.'
Back to the parasites:
Most of these parasites and pathogens are types of worms. So in the following text I refer to ‘worms’ but mean this whole group of intestinal disorders caused by worms, other parasites, and some bacteria. Thus, I’ve used the word de-worming to describe the curing of marine fish of these invaders.
If the fishes are de-wormed (which is very easy to do) the aquarist does not have to worry about the worms taking nutrients away from their fishes.
Unfortunately, it isn't easy to always tell if a fish has these worms. The symptoms of a worm infestation match other intestinal disorders. Generally though, the symptoms and observations of fishes with intestinal worms include:
Strange feces (stringy, solid lengths, colored wrong, worms in feces, etc.)
Appearance of worms at vent (anal opening)
Fish eats voraciously (the proper foods) but doesn’t seem to gain weight
Fish eats but is losing weight, or seems to be wasting away
Fish eats but is losing coloration and clear marking boundaries
Fish eating habits have changed to picking at foods or it stops eating
Unfortunately, if allowed to go uncorrected, the fish could just stop eating or never start to eat when it gets to the hobbyist.
Obviously the above set of symptoms can apply to certain other conditions, however, the strange feces is the one symptom you'll come to rely upon most, for this diagnosis. You have to be a Super Pooper Snooper to sniff out the problem.
I would like to cover in this post the three most common problems which are indicated by the above symptoms.
There are three (3) basic possibilities when it comes to an intestinal problem. I'm getting only a little bit more technical here. The three groups or culprits for intestinal disorders are:
Bacteria
Parasitic Worms
Dinoflagellates
Each has a 'favorite' remedy or medication. For the inexperienced hobbyist, separating the three may be difficult. However, the majority of the time, when the fecal matter is evident of an intestinal organism, it is a parasitic worm of some kind.
Garlic is not a remedy. It has been suspected of helping in one case of internal parasites, but hasn't been found to be reproducible. The fish was fed solid chunks of it. Garlic juice does nothing in this case.
Knowing how long you have had this fish would help in determining which of the three is the culprit. If you kept the fish in quarantine when it was acquired, this will help in trying to separate which of the culprits is at work. Since I don't know this information when I wrote this post, I have to assume either possibility and provide how to deal with each.
Whatever the intestinal problem, the fish needs the best water quality and the best diet AND supplements added to its diet. Remember, it is eating for two or two thousand!
If the fish is not eating then the only way to get medication to the intestinal track is to put the fish in a quarantine tank and treat the water with chemicals that will kill the internal condition. The drug Praziquantel (a.k.a. Droncit) will treat intestinal worms (see below for other suggestions), Maracyn Two for Saltwater fish will treat an internal bacterial infection and Metronizazole will treat dinoflagellate infections.
To be conservative: I recommend either of two ways forward:
1. If you've had your fish for several months or more: First check your source water for contaminants. Use only the best source water and make up a new batch of salt water. Now check that freshly made up water for quality/contaminants. If it passes, then adjust it for pH, temperature and salinity, mix some more, then do an 80% water change and see if the fish seems to 'perk up' (e.g., starts eating or eats more or swims around more in the open). If the fish definitely perks up then it maybe a combo of water conditions and bacteria. In this case, I'd treat the fish for an internal bacterial infection. Move fish to a hospital/quarantine tank and treat with Maracyn Two for Saltwater fishes. Begin with a double dose and continue double dosing what is recommended on the medicine insert. With proper nutrition and water quality, the fish may gain control and conquer the internal infection.
2. If you recently acquired the fish: Treat the fish for worms (using Praziquantel or an alternate noted below) first and if no improvement, treat for dinoflagellates (using a medication containing Metronizazole). You can use a medication that includes both these (see below).
If the fish was fat and eating properly and being fed a proper diet, including vitamin and fat supplements, then the fish can live without eating for several weeks, providing all other environmental and water quality conditions are as they should be and the fish is not otherwise diseased. Praziquantel is best administered orally so if your fish isn't eating, try to get the fish eating.
De-worm all newly acquired fishes with Praziquantel (or one of the given alternative drugs given below) right after acclimation and as soon as the fish begins to eat.
Dose Praziquantel (or an alternate drug) as instructed below. Wait 6 days and dose again. This treatment is over!
----------
Medications:
Maracyn Two for Saltwater fishes. Made by Mardel. Contains the antibiotic Minocycline with B complex vitamins (to stimulate appetite). Available at some LFSs, Petco, and on line.
------------------
Praziquantel. Praziquantel may be hard to find. But it is available on-line along with other medications at: National Fish Pharmaceuticals, FISH DISEASE . . It is also available on-line from PondRX PondRX - Home. . Unfortunately, the quantity of Praziquantel you need to order as a minimum order may be more than you'll need in the next few years. Search for more places though for smaller quantities or split the smallest container with other hobbyists/club members.
USE OF PRAZIQUANTEL: It is administered at 23mg per pound of fish, in their normal food. Wait 6 days, then treat again. Verify the 'cure' by observing the faces form/shape. There is no need to move the fish to a quarantine/hospital tank. The fish can be treated wherever it is, so long as you are putting the medication into the food.
There is a commercially prepared anti-parasitic pellet food available. It is made by Jungle. The product name is: Anti-Parasite Medicated Fish Food. The active ingredients in this food are levamisole (also a stimulant for the fish immune system), Metrodinazole, and Praziquantel. This particular formula will kill a much broader spectrum of intestinal organisms. Follow package directions or add some to food.
The aquarist is looking for a treatment that the fish will swallow (not a water treatment). However, if the fish isn't eating, the water treatment is necessary. Follow directions that comes with these alternate medications.
Alternative Meds (overseas). I try to be on the look-out for meds available outside North America. I've recently come across some that are suitable for de-worming. Those aquarists in the UK and Europe may find Fenbendazole or Piperazine more readily available. They are dosed at 250mg/100g of food, fed for 7 to 10 days. Medications containing these will likely come with dosing instructions. Follow label instructions for administering these products.
-----------------
Metronizazole. Also found in several products. (See above). Follow the directions that come with the medication.
BE A SUPER POOPER SNOOPER. Watch your fishes' feces! (This is a hobby? )
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