Breeding Guppies and Mollies for Saltwater Predators?

[YOYOYOReefer]

My predator tank eats anything you put in it, including your fingers lol.
Its best to really research everything you can about the diet of your particular fish. Each of my predator fish is like a dog or cat to me. Ive had one of my eels at least 10 years. Some of the predator species can live quite long.

 

[nuxx]

My predator tank eats anything you put in it, including your fingers lol.
Its best to really research everything you can about the diet of your particular fish. Each of my predator fish is like a dog or cat to me. Ive had one of my eels at least 10 years. Some of the predator species can live quite long.

Had a Skeletor eel back in the day, was a sweetheart...

Always toyed with the idea of a dragon eel though...

 

[lion king]

When we change fish over to non-living foods, we also supplement with vitamin E and Thiamin. The only longevity issues we still see is in lionfish and anglerfish and that is likely from over feeding and fatty acid profile issues. Everything else lives to expected longevity (or longer) with no live foods at all.

Jay

Even lions will live a decade or more if they will actually accept the foods that include a fatty fish and people offer quality food, like fresh when possible, and whole shrimp not shelled and deveined. The problem is many lion species won't accept these foods, with the exception of the volitan. Very easy to keep volitans more than a decade if offered the proper quality foods. Same with eels, include fatty fish and fresh when possible, whole shrimp; old frozen shrimp has lost much of it's nutrition. The only ones I am adamnet about feeding live are most scorps, dwarf and medium bodied lions, anglers, and some of the other ambush predators like goblins and robins. Also providing not overfeeding, usually by feeding too often in the case of the ambush predators.

Why do people still miss it, moray eels live over 20 years in the wild. Notable source confirm in captivity its about 2 years. Other than initially if necessary I never feed my volitans or eels live foods, except the ribbon eel, which again is a special case.

 

[Jay Hemdal]

Even lions will live a decade or more if they will actually accept the foods that include a fatty fish and people offer quality food, like fresh when possible, and whole shrimp not shelled and deveined. The problem is many lion species won't accept these foods, with the exception of the volitan. Very easy to keep volitans more than a decade if offered the proper quality foods. Same with eels, include fatty fish and fresh when possible, whole shrimp; old frozen shrimp has lost much of it's nutrition. The only ones I am adamnet about feeding live are most scorps, dwarf and medium bodied lions, anglers, and some of the other ambush predators like goblins and robins. Also providing not overfeeding, usually by feeding too often in the case of the ambush predators.

Why do people still miss it, moray eels live over 20 years in the wild. Notable source confirm in captivity its about 2 years. Other than initially if necessary I never feed my volitans or eels live foods, except the ribbon eel, which again is a special case.

I'm not sure why people are seeing short lifespans in morays, I never have. I agree ribbon eels are a super special case, I'll feed them anything they decide to eat (grin).

I used to feed live foods to many "tricky" species, like trumpetfish and more delicate scorps like Rhinopias. One of my staff was disdainful of this, he has a real ability to get literally ANY fish feeding on non-living food....basically, he took my giving in to live foods as a challenge and would work to get everything feeding on non-live foods, just to prove me wrong.

Ultimately, I learned from him and let him convert all of the fish over. The reason is the underlying fact that live foods always have an increased disease risk. I know that feeding FW to SW and vice-versa reduces the chance of external disease introduction, but internally, fish are fish - with the same blood salinity. This means that internal parasites such as coccidia and tapeworms can be introduced with live feeds. Freezing the food first reduces that issue. It is also more palatable to some people (understanding that others like to see their fish hunt live prey).

Here is his method, that I wrote up in my fish disease book:

Converting piscivores to feed on non-living foods​

One basic principle of life in the sea is that big fish often eat little fish. Many carnivorous fish feed exclusively on smaller fish and are termed obligate piscivores. When brought into captivity, this feeding behavior can become a liability, as small, living marine fish are too expensive to feed to larger fish on a regular basis. When one of these fish is collected and brought into captivity, it may not have fed normally for up to a month prior to that time. The first consideration is of course to get the animal feeding as usual. This often entails offering the piscivore some small live fish, which are usually accepted with much gusto. Lionfish, anglerfish, trumpetfish and many others will accept live fish quite readily from the first day they are placed into an aquarium. The question is then; can this feeding regimen be sustained? For aquarists near the ocean, this may not be a problem as they can usually collect some manner of small live fish to feed their animals. Inland aquarists have more of a problem. Buying damselfish, marine killifish or other species becomes too expensive. Mollies and Gambusia can be adapted to living in seawater and then be used as a live food source. Live feeder goldfish and guppies may be accepted, but have serious nutritional deficiencies when fed to marine fish for long periods (See thiaminase section above). If nothing else, using live fish as food is abhorrent to some aquarists, and is never really a convenient or cost-effective food source. The alternative then is to train the piscivorous fish to accept some type of non-living food. The following process has worked for every species of obligate piscivore, as long as the aquarist spends the time and effort required to allow the method to succeed:


1) The first step is to stabilize the new fish and get it to accept any live fish of appropriate size as a first meal (At the same time, general quarantine issues must be addressed). Do not allow the new fish to spend too much time at this stage. It is very common to have fish become “addicted” to one particular type of live food if it is used for too long of a time. As soon as the fish is routinely accepting live fish, and has become somewhat conditioned to associate your approach with an impending meal, it is time to try step two.

2) Using the same species of food fish that the animal is accustomed to, freeze some, then offer the animal a mixture of living, and thawed / dead fish. By chance, it will likely swallow some of the dead fish while searching out the live fish. If this fails, try impaling a live fish on a broom straw or 3/16” clear tubing and offer it to the fish that way. Once accepted, switch to impaling previously frozen fish and feed in the same manner.

3) Continue introducing more thawed whole fish to the animal’s diet each day until the animal is not being offered any live or fresh food. It may help to forcefully toss the dead fish into the aquarium so that their motion is more likely to elicit a feeding response.

4) Eventually, the predator should be feeding solely on thawed, whole fish tossed into the aquarium. At this point, use a knife and remove the head of each of the frozen fish, so that the predator then becomes accustomed to feeding on just the fish’s body. The reason for taking this step is that most piscivores clue in on their prey’s eyes as a means to make an effective capture. When the eyes of their food item are removed, this primary feeding cue is removed and they may not recognize the item as food. Once the piscivore has overcome this need, they are one step closer to being trained to feed on prepared food items.

5) The next step to take is to switch the fish to begin feeding on a different type of fish flesh such as smelt. To make this transition, use a sharp knife to cut a piece of smelt into a good facsimile of the headless fish that the animal has been used to feeding on. Drop these smelt pieces into the aquarium and they will usually be accepted with little problem.

6) At this stage, the predatory fish is usually willing to begin accepting almost any food item including prepared gelatin foods. Never allow the fish to “backslide”, avoid the temptation to give it a live fish as a treat from time to time. The fish may relapse; and you may find that you will have to start the training process all over again.

Jay

 

[lion king]

I'm not sure why people are seeing short lifespans in morays, I never have. I agree ribbon eels are a super special case, I'll feed them anything they decide to eat (grin).

I used to feed live foods to many "tricky" species, like trumpetfish and more delicate scorps like Rhinopias. One of my staff was disdainful of this, he has a real ability to get literally ANY fish feeding on non-living food....basically, he took my giving in to live foods as a challenge and would work to get everything feeding on non-live foods, just to prove me wrong.

Ultimately, I learned from him and let him convert all of the fish over. The reason is the underlying fact that live foods always have an increased disease risk. I know that feeding FW to SW and vice-versa reduces the chance of external disease introduction, but internally, fish are fish - with the same blood salinity. This means that internal parasites such as coccidia and tapeworms can be introduced with live feeds. Freezing the food first reduces that issue. It is also more palatable to some people (understanding that others like to see their fish hunt live prey).

Here is his method, that I wrote up in my fish disease book:

Converting piscivores to feed on non-living foods​

One basic principle of life in the sea is that big fish often eat little fish. Many carnivorous fish feed exclusively on smaller fish and are termed obligate piscivores. When brought into captivity, this feeding behavior can become a liability, as small, living marine fish are too expensive to feed to larger fish on a regular basis. When one of these fish is collected and brought into captivity, it may not have fed normally for up to a month prior to that time. The first consideration is of course to get the animal feeding as usual. This often entails offering the piscivore some small live fish, which are usually accepted with much gusto. Lionfish, anglerfish, trumpetfish and many others will accept live fish quite readily from the first day they are placed into an aquarium. The question is then; can this feeding regimen be sustained? For aquarists near the ocean, this may not be a problem as they can usually collect some manner of small live fish to feed their animals. Inland aquarists have more of a problem. Buying damselfish, marine killifish or other species becomes too expensive. Mollies and Gambusia can be adapted to living in seawater and then be used as a live food source. Live feeder goldfish and guppies may be accepted, but have serious nutritional deficiencies when fed to marine fish for long periods (See thiaminase section above). If nothing else, using live fish as food is abhorrent to some aquarists, and is never really a convenient or cost-effective food source. The alternative then is to train the piscivorous fish to accept some type of non-living food. The following process has worked for every species of obligate piscivore, as long as the aquarist spends the time and effort required to allow the method to succeed:


1) The first step is to stabilize the new fish and get it to accept any live fish of appropriate size as a first meal (At the same time, general quarantine issues must be addressed). Do not allow the new fish to spend too much time at this stage. It is very common to have fish become “addicted” to one particular type of live food if it is used for too long of a time. As soon as the fish is routinely accepting live fish, and has become somewhat conditioned to associate your approach with an impending meal, it is time to try step two.

2) Using the same species of food fish that the animal is accustomed to, freeze some, then offer the animal a mixture of living, and thawed / dead fish. By chance, it will likely swallow some of the dead fish while searching out the live fish. If this fails, try impaling a live fish on a broom straw or 3/16” clear tubing and offer it to the fish that way. Once accepted, switch to impaling previously frozen fish and feed in the same manner.

3) Continue introducing more thawed whole fish to the animal’s diet each day until the animal is not being offered any live or fresh food. It may help to forcefully toss the dead fish into the aquarium so that their motion is more likely to elicit a feeding response.

4) Eventually, the predator should be feeding solely on thawed, whole fish tossed into the aquarium. At this point, use a knife and remove the head of each of the frozen fish, so that the predator then becomes accustomed to feeding on just the fish’s body. The reason for taking this step is that most piscivores clue in on their prey’s eyes as a means to make an effective capture. When the eyes of their food item are removed, this primary feeding cue is removed and they may not recognize the item as food. Once the piscivore has overcome this need, they are one step closer to being trained to feed on prepared food items.

5) The next step to take is to switch the fish to begin feeding on a different type of fish flesh such as smelt. To make this transition, use a sharp knife to cut a piece of smelt into a good facsimile of the headless fish that the animal has been used to feeding on. Drop these smelt pieces into the aquarium and they will usually be accepted with little problem.

6) At this stage, the predatory fish is usually willing to begin accepting almost any food item including prepared gelatin foods. Never allow the fish to “backslide”, avoid the temptation to give it a live fish as a treat from time to time. The fish may relapse; and you may find that you will have to start the training process all over again.

Jay

Again, completely missing the point. It's the quality of the dead diet. If, and that's a big IF, they accept the foods that provide the proper nutrition, then all's well. While the biggest challenge is getting some to eat dead period, the most common foods fed to the predators we are speaking, will not satisfy their nutritional needs much more than a year or 2. Many will accept the dead food temporarily, or a limited amount that again doesn't satisfy in the long run. Some will simply refuse to eat after a while, possibly to malnutrition or a lack of enrichment that comes from the hunt. You can find studies on land predators about enrichment and the health challenges of keeping predators on a dead diet in captivity. It's certainly not impossible, just a very huge percentage of failure associated with many predators.

 

[Jay Hemdal]

Again, completely missing the point. It's the quality of the dead diet. If, and that's a big IF, they accept the foods that provide the proper nutrition, then all's well. While the biggest challenge is getting some to eat dead period, the most common foods fed to the predators we are speaking, will not satisfy their nutritional needs much more than a year or 2. Many will accept the dead food temporarily, or a limited amount that again doesn't satisfy in the long run. Some will simply refuse to eat after a while, possibly to malnutrition or a lack of enrichment that comes from the hunt. You can find studies on land predators about enrichment and the health challenges of keeping predators on a dead diet in captivity. It's certainly not impossible, just a very huge percentage of failure associated with many predators.

Sorry, I'm not sure what point I'm missing, I'm just discussing the relative merits of live versus dead feeds.

I should have clarified - our fish diets had been evaluated on an "as-fed" basis by the MSU animal nutrition lab. They did a number of studies in aquariums around the country, and their results resulted in the development of this Mazuri product:

https://pims.purinamills.com/BusinessLink/media/Mazuri/ProductSheet/0010112.pdf?ext=.pdf

Feeding typical non-living foods without this (or similar) supplementation is going to be an issue.

Regarding enrichment of feeding live foods to terrestrial carnivores, I spent 35 years working in zoos. Modern carnivore diets have no real health challenges associated with them compared to feeding whole or live prey items. The latter is done entirely for enrichment purposes. The prepared diets are more nutritionally complete. In fact, feeding live and whole prey items is more risky. I don't know how animals survive in the wild, in zoos, they choke on feathers, get bone fragments caught in their teeth, selectively eat some parts, leaving the rest, etc. Disease is also an issue if the food source isn't controlled (we freeze carcasses before feeding them out). Still, the enrichment is done because of the psychological benefits for the animal. Does that translate to fish? Yes, as evidenced by the "backsliding" we see when a fish is fed living prey and then begins refusing dead prey that it had been eating. However, IMO, the drawbacks of feeding live fish are greater than the benefits.

Jay

 

[Aspect]

Well threw a male molly and 2 females in a 40 tall about 2 months ago and haven't really checked in on them since, just been feeding them regularly. Only filter in there is an established piece of rock on top of a bubbler. Just checked in there and there's dozens of baby mollies. Pretty cool I didn't think they would breed to be honest. Anyone know how long it takes a molly to grow to adult size?

 

[RSNJReef]

I believe it will take a while for them to get to adult size (8 months). I have male guppies and female mollies in my frag tank in the basement, and I get crossbreed babies (mollies and guppies can cross breed) often in the sump of my frag tank, at least 2 or so a week that make it past the filtration system all the way to the return section of my frag tank sump. My first set is about 4 months only and only a half inch in length, and I don’t expect them to get to the size of a Molly as they are part guppy, but I think it’ll still take a while. If you feed on the heavier side it’ll speed up the growth some.

 

[Aspect]

I believe it will take a while for them to get to adult size (8 months). I have male guppies and female mollies in my frag tank in the basement, and I get crossbreed babies (mollies and guppies can cross breed) often in the sump of my frag tank, at least 2 or so a week that make it past the filtration system all the way to the return section of my frag tank sump. My first set is about 4 months only and only a half inch in length, and I don’t expect them to get to the size of a Molly as they are part guppy, but I think it’ll still take a while. If you feed on the heavier side it’ll speed up the growth some.

Crossbred mollies? Very cool. What salinity level do you keep them at?

 

[twentyleagues]

Crossbred mollies? Very cool. What salinity level do you keep them at?

Yup. They call them muppies or gollies depending on if it was a female guppie or molly giving birth. All cross bred guppies and mollies are sterile. You can get some pretty cool looking fish. I've played with them before for a couple years. I've never kept them in full saltwater before. I didn't think they would breed. Apparently I thought wrong. Mollies breed fine in brackish but guppies not so much at least for me.

 

[RSNJReef]

It might be cause I only have male guppies and female mollies (I didn’t intentionally do this, I just looked for the better looking ones and it worked out this way, the one male Molly I had had died about a month in). They are in full salinity though. What I do is put any newcomers in a 2-3 gallon container with freshwater and a rigid airline aggressively rolling the water (enough to keep the water turning but not agitate the fish), then once every morning and once every afternoon I take out 32 ounces of water and replace it with 1.027 sg water. It takes about a week to fully convert them, and I’ve read you can convert them to full sailinity in 2 days, but, I’m in no rush. Once they are fully converted, you can introduce them to your tank. My first addition to my frag tank was a Molly, and it’s been in the tank over a year and still going strong. I also have two 3-4 inch long male mollies in my bedroom tank that are about a year and a half old as well.