This article contains helpful tips, advice and techniques for stripping the eggs from an african cichlid mothbrooder. It includes step-by-step instructions about how to strip african cichlid eggs without harming the mother, equipment needed for a good fry tank and how to use an artificial incubater. The act of striping the fish of her eggs is a complicated process that involves a multitude of equipment and good timing.
The only fish you can strip are mouth brooders. The only ones that I am familiar with are African cichlids, although I am certain that the same technique can be used for other types of mouth brooding fish. A true naturalist would want the pair of fish to release the fry naturally in a perfect environment, without predators or parental problems to endanger the baby fish. This would be the best way to have fish spawn because I believe the fry learn or "it" is imprinted onto them, that this natural act makes them better parents. The parents take care of the eggs and after hatching, they take better care of the fry.
Generally the father patrols the perimeter to keep potential problems away, while the mother cares for and nurtures the young fish. If danger enters the vicinity the mother takes the fry back into her mouth, holding them in her boucle cavity, until the danger passes, she then releases them to feed and explore the area. This will continue until the pair is ready to spawn again, which can be anywhere from a few weeks to a few months. At this time they will either chase the fry away or eat them.
In an aquarium, I like to keep the mother and babies in a separate tank, with water from the spawning tank, same temperature and pH, for ten (10) days. This gives the mother a chance to build her strength up and she will not be harassed by other fish. It also provides time for the bonding process between parent and offspring. This is where the imprinting, teaching, learning, whatever you want to call "it", between parent and fry that imparts knowledge and procedures that ensures good parenting. Fry that are stripped have to re-learn this via heredity and trial and error methodology.
Too bad we don't live in a perfect world. For the aquarist there are many times when young fish are just bad parents or they were stripped from their parents prior to knowing how to be a good parent. In these cases the aquarist does not want to lose a valuable fish that is holding equally valuable fry. In many instances young parents eat or spit out their eggs prior to hatching because the male didn't fertilize the eggs, the mother is being harassed by other fish, or the mother fish may get hungry and the instinct to not eat hasn't taken control yet. The aquarist may determine that he hasn't another tank for holding the mother and fry, and/or other fish would eat the fry, if left in the original tank. The aquarist may realize that the faster he removes the eggs or fry the faster the parents will spawn again, thus increasing his stock of fry, which to him is like money in the bank. Whatever the reason, the aquarist has determined that the mother fish will be stripped of her eggs or fry. Now, how is this accomplished - successfully?
The equipment that is needed:
Hatchery tank & plastic bottles - I prefer a 10 gallon high (8" W X 16" L X 17" H). This size tank is hard to find. I like this size tank because (thanks to Tom Miglio) it can fit a portion of a Coca Cola™ plastic case holder, that is cut or sawed down to have fit 3, 2 liter plastic bottles in the large holes and 3, 1 liter or smaller plastic bottles in the small holes. In this way you can have 6 hatchery containers working simultaneously. With this method rigid airline tubing is needed with an inch or so of flexible airline tubing at the end that the airstone will go into. It is important that the airstone be at the very bottom of the plastic bottle in order for the air bubbles to move the eggs and keep them in constant motion. Use three (3) sponge filter stands to keep the Coca Cola plastic case holder off the bottom of the tank.
Another way of hatching eggs is through the use of a 1 liter plastic bottle that is aquarium sealant is applied to the bottom of the bottle and to a flat rock or piece of slate. A small hole is made at the base of the bottle where flexible airline tubing is inserted, this is worked up to the top of the bottle (where the cap usually goes) and an airstone is inserted into the tubing. The tubing is then drawn down to the base of the bottle and aquarium sealant is applied to the exterior of the hole where the tubing went in, to ensure the water from inside the bottle does not leak out. It is important that the airstone be at the very bottom of the plastic bottle in order for the air bubbles to move the eggs and keep the eggs in constant motion.
I learned this method from Joe Ferdenzi - have a 2 liter plastic bottle, invert it, cut the bottom off where the indentations start to make it a flat bottom, get a black plastic bottle holder that the 2 liter bottle fits into (it has a flat bottom with 4 holes on the edges and is 1/ 2 inches high). Place this plastic bottom over the bottom of the plastic bottle that you cut the bottom off so it will fit like a new bottom. Get a piece of rigid, flat plastic, place it on the top of the bottle and use aquarium sealant to secure the inverted bottle to the flat plastic piece. Get a piece of rigid airline tubing with a inch of flexible airline tubing at the end that an airstone will go into, insert the rigid tubing through one of the holes in the base of the black plastic bottle holder. It is important that the airstone be at the very bottom of the plastic bottle in order for the air bubbles to move the eggs and keep the eggs in constant motion.
With the last two methods using single bottles, a regular 20 gallon tank (13" W X 17" H X 24" L) would suffice. You need tanks of this size to keep the water temperature the same, both inside and outside the bottle and the bottle should be 60% filled with the original tank water. It is very important to ensure the eggs or fry have the exact same water conditions as in the tank they came from.
The plastic hatchery bottle is representing mom's mouth as she would constantly rotate the eggs and/or fry with their yolk sack. This ensures that each egg obtains equal amount of water, heat and rotation to have a successful egg incubation.
Important note - when using aquarium sealant always apply it in an open, air circulating area and always let the applied sealant dry and harden for 2 days.
Net - the net must be large enough to catch and hold the mother fish, yet the holes must be small enough so that the eggs do not fall through. I recommend the use of two nets, because the mother must be caught quickly before she tires and panics where she might eat the eggs or fry or worse spit them out into the tank full of hungry predators.
Heater - this is one of the most important devices you can buy for your baby fish. DO NOT GO FOR A CHEAP HEATER. I prefer submersible heaters such as Ebo-Jager or other high quality heaters. Always wrap airline tubing around the heater coil so that if fry swim against the heater they won't disintegrate. Baby fish are drawn to heaters because of its light and the heat given off, the problem is It works like a moth to a bug zapper. If you have airline tubing around the heaters coil it won't burn the fish. The airline tubing will not effect the temperature of the tank or harm the heater.
Acriflavine or Methylene Blue - anti-fungus medicine. With Acriflavine you turn the water yellow and also your fingers and with Methylene Blue you turn the water blue and also your fingers. Both are manufactured by Kordon. This is a must for eggs that haven't started developing yet. Nothing hits eggs faster than fungus. Unfertilized eggs are the first to be hit with fungus and because of the sticky quality of the eggs the fungus will attack fertile eggs as well. I recommend using as little of the medication as possible. One half of a drop to one drop maximum; you want a slight discoloration of the water in the plastic bottle. After a day or so, when the eggs start developing, start water changes of 10 - 20%, to reduce the amount of anti-fungus medicine in the bottle and always use water from the original tank to refill the hatchery bottle. Once the embryo has fully developed and is about to hatch, have clean water from the original tank, with no medication in it, for the fry to emerge into.
Aerator - have a good quality aerator that can easily put air into a couple of these bottles. Have the airline tubing that connects to the aerator work with a gang valve. In this way the air bubbles can be controlled for less or greater intensity. This control of the air bubbles will be crucial to the correct tumbling of the eggs. Too great of an air flow and the eggs become damaged and break by bouncing around too much. If there is not enough airflow then the eggs are not moving and they stay in one place, this prevents the eggs to have a continuous flow of water and air flowing around the egg, which destroys the embryo.
Container to hold eggs I prefer a small container such as a plastic soup container from a Chinese restaurant. You could also use something the size of a Betta bowl. Once you strip the fish of her eggs and the eggs go into the net you need to move them from the net into this holding container. I prefer not to have the eggs hit the air. Submerse the container into the tank and then move the net containing the eggs over the container and then invert the net so the eggs drop into the container, which has the water from the tank in the container. Now you can remove the eggs from the tank safely and put them into the hatchery bottle.
All right, now you have all the ingredients so you are ready to catch the moma fish and strip her of the eggs. Using two nets in a slow fashion try to isolate the fish to an area such as a side glass or front glass where there is little obstruction in the way. You may have to remove rocks and ornaments prior to trying to catch the fish as this will make it easier for you and the fish.
Catch the fish in the net and then with your left hand (if you are right handed) hold the fish securely, but not tight, with the head pointed down into the net, remove the fish half of the way out of the water having only it's gills and mouth in the water. With your right hand using a fingernail or a two (2) inch piece of airline tubing that has been cut diagonally on one side to have a pointed tip, insert either the cut airline tubing or your fingernail into the mouth of the fish just enough to be able to secure a grip on the bottom lip.
Apply gentle pressure to pull the lip down so that the mouth is fully opened. This will cause the eggs or fry to tumble out and into the net. This action may have to be done several times to ensure all the eggs /fry have been removed and to provide the mother fish with a rest by easing her back into the water in the net, but never release your hold on the fish. Once you have ascertained that all the eggs or fry have been released you remove the mother fish from the net and gently place her back into the same tank she came from. Slowly release your grip on the fish but gently hold her until she has regained enough strength to swim away on her own.
Now comes the tricky part - you must have the container close by and available immediately, because if you have to leave the eggs or fry in the net for more than a minute the other fish in the tank will eat them right through the net. Move them quickly into the container and then to the hatchery. When the eggs are in the hatchery and if all goes well you will see the eggs develop into fish and then emerge from their egg casing. African cichlid fry usually emerge between 27 and 30 days from the day of starting life's journey in mom's mouth. If you notice eggs that are not developing, they stay the same color or become paler or lighter - then those eggs are not fertile and must be removed immediately, because they will fungus and contaminate the rest of the eggs.
Important note - if the eggs stay in moms mouth for 14 days then generally she will carry the brood to full term and will release the fry when they are ready. If you happen to strip mom of eggs after 14 days the embryos are already formed and you stand a much greater chance for the eggs to hatch. Any time an egg has less time in a hatchery it will be better for the egg and for your chance of success.
When the fry emerges from the egg they will have an egg sack on their stomach. Do Not Feed The Fish Until The Egg Sack Is Gone, usually within a week. Once the fry have emerged from the egg and are hopping around they can be moved to a "rearing tank". A rearing tank is a small tank, usually 5 gallon capacity.
This aquarium should have good quality heater in it, proportionate to the size of the tank, with the heating coil wrapped in airline tubing. It should also have a sponge filter, with a solid base to it, so that the sponge may not be able to fall to the bottom of the tank and possible hurt any slow moving fry. There should be no gravel in this tank; this will make it easier to keep the tank clean. The water in the tank must have come from the parent's tank. After the first week or so, depending on the species, start a 10 - 20% water change using tap water that has been conditioned. By conditioned I mean to add declorinator to the tap water to remove the chlorine and any other metals that may be harmful to the baby fish.
Once the babies egg sack has disappeared and they are swimming normally you can start the fry on baby flake food, baby brine shrimp, live daphnia or other high quality foods. If the mother holds the fish in her mouth to full term the fry will have absorbed the egg sack and will emerge from mom's mouth very hungry. In this case start feeding immediately. The food you feed the baby usually is not the same type food you feed to mom and dad fish. This is because the needs of the fry are different from the parents. Feed foods rich in protein and vitamins and with a higher fat content in order for the fry to "bulk up" quickly. If possible feed your fry 2 or 3 times per day, but in very small amounts. This will assist them in growing faster. As with all young fish the first 30 days are crucial to their survival.
Once the fish get larger (triple their original size) it is time to move them to a "grow out tank" which usually is a 20 - 30 gallon tank for the fish to get larger, faster. It is also important to note that fish can be cannibalistic, always try to keep the same size fish together. Take the larger fish and place them into smaller tanks in order for their siblings to catch up with the growth process.
And that's it! Pretty simple process really, providing your fast and know exactly what to look for. Good luck in your stripping program.