How to Make DIY Spawning Mops for Breeding Aquarium Fish

Many aquarium fish like to lay their eggs by scattering them or sticking them onto plants and various surfaces. To protect the eggs from being eaten and improve the survival rate of baby fish, veteran breeders often make spawning mops for the fish to deposit their eggs. Unlike live aquarium plants, this artificial spawning media does not require any light or fertilizer, and they are quite easy to transport without breaking any plant leaves or roots. People even use them with livebearers (or fish that bear live young) because the many strands of the mop provide dense cover for the fry to hide between. These are the steps to make two types of spawning mop for your aquarium fish.

Instructions for Yarn Spawning Mop

This popular spawning mop can be used with rainbowfish, goldfish, tetras and barbs. Depending on the species you are breeding, you can make a floating mop, sinking mop, or a mop that attaches to the tank wall.

1. Gather the materials 100% acrylic yarn 2. Cork (for a floating mop), small rock (for a sinking mop), or suction cup (for a mop that attaches to the tank wall or bottom) 3. Flat, hard object of the desired height (e.g. notebook, book, Bluray case or piece cardboard). Scissors

1. Wrap the yarn around the notebook about 40 to 100 times and then cut off the rest of the yarn.

1. Use a length of yarn measuring 12 to 24 inches to tie the yarn strands around the notebook.

1. Slide the yarn strands off the notebook and cut the loops at the opposite end of the yarn knot. Trim the mop if you find that the yarn strands have become too long or are not even.

1. Then, tie the excess knots around the rock, cork, or suction cup.

1. The mop should be rinsed in tap water. 2. Depending on which species you are using, wait several days to two weeks after fish have spawned. Move the eggs from the mop into a container with an air stone or breeder net. Some people will transport the whole spawning mop and eggs together, while others prefer to remove the eggs using their fingers or tweezers.

Instructions for Ricefish Spawning Mop

Regular yarn mops do not work as well for certain species like Japanese medaka ricefish because the yarn strands are too free-flowing. For the eggs to be released from rice fish, stiffer bristles are needed to rub against.

1. Gather the following materials: Pool noodle with a hollow hole in the center 2. Scotch-Brite pads (with no cleaning chemicals in them) 3. Cutlery and kitchen knife 4. Scissors

1. With a knife or a cutting board, cut a 1/2-inch circle from the pool noodle.

1. One pad can be used. Position it horizontally in landscape orientation. Begin at one of the corners of the pad. Make a vertical cut upwards, stopping approximately 1/2″ from the top. You will create the “strands” by making multiple vertical cuts along the bottom of your pad.

1. Roll the pad up so the pad’s top 1/2″ looks like a spiral. The bottom 1/2″ of the pad is like a skirt.

1. Stick the spiral end the mop through middle of pool noodle disc.

1. Place the spawning mop in the aquarium and rinse it with no soap.

1. After spawning has taken place, you can move the eggs, whole spawning mop, into a separate grow-out tank, or breeder net.

All the best with your breeding endeavors. To help your aquarium hobby, you might consider selling any fish that you have raised to the fish shop or other fishkeepers. Learn more in our article on How to Breed Aquarium Fish for Profit.