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By David E. Boruchowitz
Cichlids demonstrate extremely sophisticated reproductive strategies. One of the least common involves cooperative breeding in groups or colonies. Lake Tanganyikan Neolamprologus pulcher breed en masse, with the entire colony rising as one to fend off predators, and with non breeding individuals participating in the care and protection of the offspring.
Aquarists have long known about this behavior, which is more obvious in the wild, where hundreds of fish are involved, but which translates in captivity into breeding groups that avoid the typical predation on the fry by non parental adults in the same tank.
A new study reveals that about 10 percent of the fry produced in these colonies are sired by subordinate males, and that those males are more diligent in protecting the young.
This is reminiscent of the situation in several Xiphophorus swordtails, where smaller, inconspicuous males rely on sneaking rather than courtship to father a small percentage of fry. In both cases subordinate males father a small but significant number of offspring, though in the case of the swordtails it is a matter of genetic castes among the males, not just one of dominance.
By Ted Judy
Twenty years ago I kept and bred a lot of Lake Malawi cichlids. It is hard to beat the riot of color in a well-stocked Malawi community. Matthew (my 7-year-old fish fanatic in the making) discovered this colorful genre about a year ago, and has been slowly taking over tank space in the house ever since. We are up to three Malawi community tanks: a 42-gallon bow front in Matthew’s room, a 55-gallon in the family room, and a 40-gallon breeder in the fish room. I decided to take advantage of these three tanks for the contest by converting the tanks from purely aesthetic communities into breeding colonies.
What is the difference between a community and a breeding colony? A community can be any mix of fish regardless of sex ratio, age and compatibility (though I would hope they all can get along). A breeding colony is a group of fish set up to encourage breeding. There is some cross over. Purists and serious breeders will usually set up single-species colonies with only one or two males and many females. These large colonies will usually produce a lot of fry, but only of one species. Matthew and I chose to sacrifice large numbers of fry in hopes of getting multiple species to breed in the same tank.
The trick is to set up groups of fish that are compatible, but are not so similar that hybridization is likely to occur. Luckily there are so many different Lake Malawi cichlids that finding a good mix is not too hard to do. The two main breeding tanks are the 42-gallon bow front and the 55-gallon. The 40-breeder in the fish room has one species old enough to spawn (Labeotropheus trewavasae “Mphanga”) and a bunch of young fish that are growing up to be the next groups to go into the spawning tanks.
The 42-gallon tank has a quad (one male and three females) of adult Aulonacara stuartgranti ‘Ngara’ peacocks, a trio of Metriaclima sp. “white top Hara” and a trio of the electric blue “johanni” Melanochromis cyaneorhabdos. We had to get rid of a few single males of different species and find some females to fill out the colonies. We also added a lot more hiding places, which we did very inexpensively by asking the local plant nursery for any large damaged flower pots. Matthew is very good at getting free broken pots, which we broke more until they would fit in the tank. A big pile of the curving terra cotta pieces is perfect for these cichlids.
The 55-gallon has a quad of large OB Labeotropheus fuellebourni, a group of eight (two males, six females) Metriaclima sp. “Msobo,” and a trio of Pseudotropheus sp. “red cheek.” I am a little concerned about hybridization between the Pseudotropheus and Metriaclima, but I have not seen any evidence of it happening. In my experience, if there are suitable mates of the same species for all the fish in the tank hybrid breeding rarely occurs. I will hope for the best and pay careful attention to the fry.
The colonies were set up before the contest started, but we only had one species spawn right away: Metriaclima sp. “Msobo.” Nothing else spawned in the next two months. I started feeding more heavily and doing large water changes more frequently. Once every two weeks I would do a really large water change followed by a 4-day fast. Sometimes the lack of the diversion of food will trigger fish to spawn. The weather started to get cooler, and that is not conducive to getting Malawi fish to breed, so I was worried that I would not see any success until spring. So the first week of December I added a big heater to each tank and jumped the temperature up to 82F in hopes of heading off a winter lull. I normally do not keep my tanks much above 74F. I believe that cooler water is better for the health of the fish (assuming the fish are not ‘hot water’ species). I also went out onto my local club’s forum and asked for advice. Everyone said to split the communities up and go back to one species per tank.
I was about to do that when everything started to spawn. Within three days we had holding females of the L. trewavasae “Mphanga,” L. feullebourni, A. stuartgranti “Ngara,” Melanochromis cyaneorhabdos, and Metriaclima sp. “white top Hara.” Five out of seven is not bad, and since the M. sp. “Msobo” spawned early in the competition we are left with only one species of breeding-age Malawi cichlid to spawn.
The plan now is to rotate the species that have spawned out and new species in. Matthew is excited… he LOVES to shop for fish (the apple does not fall far from the tree).
By Ted Judy
There are many species of tetras, barbs and danios that are not difficult to spawn. A good rule of thumb to figuring out a species’ difficulty is to compare prices at a fish store. Fish that are common and inexpensive are most often farm raised and easy to breed. The poster-fish for this group is the zebra danio Danio rerio. There are two challenges for the hobbyist breeder when working with these species. First, collecting the eggs can be impossible if the breeding tank is not set up to catch eggs. Second, raising the very small fry can be a challenge without the right foods ready when they are needed.
I breed most of the tetras, barbs and danios in 2.5 gallon tank. When the fish are very small, and lay a lot of eggs, I usually put a lot of yarn mops in the tanks. After a few days the fish have deposited plenty of eggs in the yarn. Some will get eaten, but there are enough hidden in the mops to meet my modest requirements (I do not really need or want more than a dozen fry). Larger species tend to be better at eating their eggs, so I use a false bottom in the tank made from a piece of plastic needle-point mesh cut to fit into the 2.5-gallon tank. I cut the screen so that it drapes in the bottom. I use a couple pieces of PVC to hold the plastic off of the glass.
Once the screen is in place I add plants or yarn as a place for the fish to spawn. The eggs filter through the plants and then fall through the plastic mesh. Since the bottom of the tank is bare the eggs easily seen. After the eggs are laid I remove the fish, screen and pvc. I leave the plants and add a drop or two of methylene blue. I cover the top of the tank with a piece of cardboard to block the light. Most species’ eggs hatch in less than three days, and the fry are ready to eat a day later.
The first food I use is paramecium. If you do not have a paramecium culture there are products on the market, called fry foods, which are designed to provide small particles for baby fish. A good supplement to a food product is ‘sponge grunge’. Squeeze a well established sponge filter into the tank with the fry and some plants. The microorganisms in the sponge will start a colony that will feed to fry. After a few days the fry can eat microworms. One trick I use is to keep my microworm cultures very wet, about the consistency of a thick soup. The media in the culture contains all different sizes of the nematodes. When I feed from the culture, I scoop a little of the media onto my finger and swirl it into the tank with the fry. Yes, it clouds the water… but the fry do not care, and they are getting very small food.
After a week most fry can eat baby brine shrimp and they are off to the races. With lots of food and frequent water changes they will grow fast.
I have ten 2.5-gallon breeding tanks in my fish room. From spawn to relocating the fry to a growout tank tanks about 10 – 15 days. If everything works out perfectly I could breed 20 – 30 species of ‘easy’ tetras, barbs and danios in thirty days. Plans rarely work out perfectly, however, and I am happy to be successful with 5 – 10 successful spawns each month.
By Mike Hellweg
Fish will do what comes naturally and spawn in our aquaria IF we give them what they need. With many species that means approximating the spawning season, giving the adults what barb and tetra guru Randy Carey calls a “trigger” to initiate spawning. Following the metaphor, all we as aquarists need to do is figure out how to turn off the safety and pull the trigger.
With many fish like cichlids and livebearers, all we have to do is buy a group of juveniles and grow them out. Eventually, they will reach sexual maturity and pair off, even in a community tank. Often they will even successfully raise a brood of fry in that same community tank. But many other fish aren’t so easy. Many of them require a little to a lot of extra work on the part of the hobbyist.
With these fish it is best to separate out the males from the females. When you have limited tank space, the best way to do this is to move the female(s) to what will become the spawning tank, and leave the male(s) in the community tank.
At first the spawning tank can have water similar to the main tank. As the conditioning period goes forward, begin changing the water out with water more appropriate for the particular species (harder, softer, more basic or acidic, more or less salty, etc.). Do several water changes over the course of a week to 10 days.
Feed the adults heavily with meaty foods. Flake or pellet food just isn’t enough. There are various enzymes, amino acids, and other things in living foods that are destroyed by processing. This is why every experienced breeder will tell you that you need to use live foods for conditioning. Many of us use frozen and freeze-dried foods as well, but live foods really provide that extra boost that makes the difference between success and failure.
Every time I give a talk on breeding fish, I quote my friend and breeding guru Charley Grimes of Indianapolis. I think he put it most succinctly: “the best way to put eggs in her belly is to put worms in her tummy.”
Worms are an excellent live food. We are fortunate in that we have many different types of worms to use that can be sized to the mouth of the fish, or larger worms can be cut up for feeding smaller fish. Some of the ones currently in use by breeders include Grindal worms, white worms, tubifex worms, Dero worms, black worms, red wigglers, European drift worms, and night crawlers. All can be found in a local pet shop or bait store, or they can usually order them for you. If not, members of a local aquarium or herp club likely can supply starter cultures and information on how to culture them. Or you can go to various sites on the web and order them from reputable growers. Of course, you can also read my book Culturing Live Foods (T.F.H. Publications, 2008) for tips on starting many different types of live food cultures.
Most breeders culture their own live foods. There is a lot of excellent information out there about culturing live foods, including several excellent books. Culturing your own foods gives you a chance to control every aspect of your fish’s diet. More on this later…
By Mike Hellweg
When Ted first approached me with the idea for this contest, I jumped at the chance to help promote my favorite part of the hobby, breeding fish. I knew I would have to step up my game a bit (Ted is a fierce competitor!), but that also would require some modifications to my fishroom.
First, I needed to have a place for all of the fry to grow out. After all, if I was going to participate in this contest, I would also want to support my own club (the Missouri Aquarium Society, Inc. [MASI]) in our Breeders Award Program (BAP). But that would mean holding the fry for 60 days. I know, our contest rules include growing them out to 30 days, which is generally the safe point from which you know the fry will survive, but my club requires them to be at least 60 days old. That means I have to tie up tanks for twice as long as Ted. But it also means my fry will be closer to saleable size when I turn them in, so I can get them to local shops at this time, too.
I know some readers will want to know more about my fishroom. It is approximately 12 feet by 14 feet. In the walls and ceiling I installed R-30 insulation to cut down on heating and cooling costs. It is heated and cooled with our home’s central air and heating. This means I don’t have to worry too much about temperature control in individual tanks. For electrical supply in the room, I added three extra ground fault circuit interrupters (GFCI) protected circuits just for the fishroom. One is on a timer and runs the lights, another is on all the time and is for any extra filters/heaters that I might need, and the third is extra, in case I want to run something extra at some point. All of the tanks are filtered with air driven sponge filters powered by a linear piston air pump, and all of them contain live plants.
All of the tanks are drilled with overflows that go to a floor drain, so water changes are easy; I just run a hose from my 220 gallon water holding system to each tank for a few minutes and let the old water flow into the drain. This system consists of four 55 gallon drums plumbed together. The water is treated, heated, aerated and circulated between the drums until needed. If a tank needs a bit more cleaning, I can drain individual tanks into a line that runs around the room and goes to the floor drain. I can also add hang on filters if needed, but I only use these when I need to clean a tank. Lighting is supplied by power compact florescent lights and by low power consumption commercial shoplights. To control humidity and prevent mold growth, I also added an exhaust fan that turns on automatically when the room humidity gets above 50%. This just dumps the humid air to the outside, and pulls in fresh, conditioned air from the rest of the house.
In my fishroom, I have a dozen 30-gallon breeders. Those are excellent grow out tanks, each will hold dozens or even hundreds of fry, depending on the species. I can even grow out fry of several species in one tank, if they are compatible in size and temperament. But even so, that means I can only grow out a dozen or so species at a time. I need more room. Fortunately, I have eight more 30-gallon “box” tanks from a local wholesaler that went out of business a few years ago that have just been sitting there, waiting for me to come up with something to do with them. They are called “box” tanks because they are shaped like a fish box – just a bit larger – two foot square and just under a foot deep. They are used in the trade to hold a box of fish each. With their large surface area and shallow depth, they can be stacked four high in the fishroom. This rack of tanks will only take up 8 square feet of floor space while giving me 32 square feet of tank floor space! This is perfect for my fishroom, where space is at a premium. So I begin this month setting up this rack up and starting to get these tanks ready to go.
I also started conditioning fish for spawning. That means tanks for males and tanks for females in many species. I have a rack that holds 5 x 10 gallon tanks and 8 x 20 gallon “high” tanks that I designed for this purpose. It will also give me extra room to isolate new fish (every fish, invert, and new plant coming into my fishroom gets at least one month’s quarantine) and rotate extra pairs in case I have to separate fish from the main pairs in the breeding tanks.
With other fish, conditioning just means setting up a tank with proper conditions and feeding them well, while letting nature take its course. I have a wall of tanks set up just for this – a 30 long, 6 x 29 gallon tanks, 6 x 20 longs, 7 x 10 gallon tanks and 3 x 5 gallon cubes. These will be used for most of my breeding attempts.
I have a set of extra grow out tanks in case things get out of hand and I get lucky with spawnings. This consists of 4 x ½ ten gallon tanks (a specially made tank), 5 x 10 gallon tanks, 2 x 20 flats (made from two ten gallon tanks glued together – one with the back out and the other with the front out), and two fifty gallon flats (essentially a 75 gallon tank cut down to a foot deep). In addition, outside of the fishroom I have setups for larger fish. I have 7 forty breeders, a 58 breeder, and two 75’s.
Finally, the last group of tanks will be my “secret weapon” that I plan to roll out in month two or month three. More on that later – I don’t want to give too much away to Ted!
MELBOURNE, Victoria — After studying male desert goby fish, a team of Monash researchers has suggested that male sexual behavior is primed to produce the greatest number of offspring.
In the underwater world of desert goby fish, it is the males whose work is never done.
As exclusive parental guardians it is up to males to guard and fan the eggs – keeping them well-oxygenated and removing debris – while females flit about finding new mates.
Photo:P. Andreas Svensson.
Posted June 1st, 2015. Add a comment
By Mike Hellweg
The past several weeks have been pretty hectic with two speaking trips and several club auctions here in the Midwest, not to mention a visit to my local club (the Missouri Aquarium Society, Inc. – aka MASI) by TFH Editor David Boruchowitz. All of this fishy stuff, along with a LOT of spawning activity and changing over sponge filters in my fishroom, kept me pretty busy. Time slipped away, and I realized I hadn’t posted a blog in quite a while. I apologize!
As I mentioned last entry, I spent some time trading fish and visiting local big box stores and independent fish stores, and I came home with a nice haul. Unfortunately, as can sometimes be expected in the dead of winter, some of those fish were cold stressed and came down with ich. Placing fish into quarantine helped and within a week or so I was back to concentrating on breeding the new fish.
I went back to my roots in the hobby—some of the miniature scatterers like zebra, leopard, and pearl danios, white clouds, and some easy tetras like emperors, rainbow emperors, black skirt, and diamond tetras just to name a few. I had forgotten how much fun it can be to have a tank full of miniature zebras darting every which way and attacking the food every time I fed them! White clouds are one of my all time favorite fish, and it’s been a while since I had them. I now have a 10-gallon colony tank full of them. It may sound strange to some of you, but some of the most pleasurable fish are also some of the easiest to care for and breed.
Ever since my beloved pet lungfish took a chunk out of my hand, I have not kept any fish larger than 4 inches, and the vast majority have been under 2 inches. This was also practical, since for many years my fishroom was in a spare bedroom and the floor couldn’t take a lot of weight, so in order to have several tanks they had to be small. This became my trademark— miniature odd balls.
I mention this because I deviated from this longtime philosophy for a few weeks. A friend brought several pairs of medium sized cichlids over and they reminded me once again why I keep miniature fish. So I have to thank him, in a way, for reminding me of my real interest. The Texas cichlids spawned quickly and repeatedly. They are incredibly beautiful fish, but also incredibly aggressive by my standards. The West African Stomatepia mariae spawned and then went on a killing spree. The larger male Lake Victorian haps (Matumbi hunters) “went cichlid” on each other and all of the other haps in their tank. Everything was fine in this tank. A female was holding, so I gently removed her in a clear glass bowl to give her some peace and quiet in her own tank to brood for a few days before stripping the eggs. Overnight, the big male decided that he didn’t like something. Not sure what.
I’ve still got one tank of seven 9-inch Oreochromis niloticus, but as soon as they spawn, they will move on to another friend in our club who loves fish like this and has much more room for them. Right now they are happily eating everything I feed them in a 75-gallon tank, and each fish has grown at least an inch since I got the group about four weeks ago. I hope they spawn soon! I was amazed by these fish. They are beautiful, very outgoing, and they eat EVERYTHING! They even lift their entire head out of the water when I open the tank top to feed them. Pretty cool, but definitely not my cup of tea. They cleared the side and back glass of years’ worth of algae growth, cleaned out a well established blackworm population in the gravel, and even ate the Java fern and Java moss in the tank!
More next week…
Posted April 20th, 2010. Add a comment
Ted Judy, in a moment of utter foolishness, challenged Mike Hellweg to a one-on-one fish breeding contest. The rules are simple: spawn fish, raise the fry to an age when they can be safely given to another hobbyist, and repeat. The species that are spawned will be assigned point values based on the system used by the Missouri Aquarium Society, Inc.’s (MASI) Breeders Award Program (BAP), which ranks fish based upon their breeding difficulty.
The contest is to span one year, beginning with the January 2010 issue of TFH and ending with the December 2010 issue. Ted and Mike will submit a spawning report to TFH each month, as well as talk about the strategies, successes, and failures they experience during the competition. Our intrepid breeders will also update a blog at www.tfhmagazine.com/blogs so readers can get more frequent updates on what is going on in Mike’s and Ted’s fishrooms. TFH recently sat down with these master breeders to get some information about the contest, and learn a little more about the contestants: