How to Treat Parasites in Aquarium Fish

When you buy an aquarium fish, did you know that it has traveled from a fish farm to a wholesaler to a pet store before it got to you? This means that your fish could have acquired an internal or external parasite. Wild-caught fish are more likely to have multiple parasites. Unfortunately, most of the time aquarium fish don’t stay at the store long enough to make sure they are free of parasitic diseases. The following antiparasitic medications may be necessary to treat visible parasites, discolored poop, slimming, or skinny fish.

1. Ich-X

Hikari are well-known for making high-quality fish meals. However, they also produce great fish medications under the Pond Solutions and Aquarium Solutions product lines. After testing dozens of ich medicines in the United States, we have determined that Ich-X is one of the most effective formulations for treating ich (or white spot disease), other external protozoan parasites, and mild fungal infections. In fact, we use Ich-X to proactively treat all fish that enter our fish store before they get sold to customers. It contains formaldehyde as well as malachite blue chloride. It is safe to use on scaleless fish, invertebrates and live plants.

If your fish looks like it’s covered in little, white grains of salt, it could be ich and needs to be treated immediately. It’s important to have Ich-X and other first-aid medications on hand.

There are two types: Aquarium Solutions IchX for small aquariums, and Pond Solutions IchX for larger tanks with 50 gallons and more. To use Aquarium Solutions Ich-X, follow these steps:

1. Clean the aquarium and do a water change. Take out any chemicals (such as activated carbon and Purigen) or UV sterilizers. 2. For every 10 gallons of aquarium water, add 1 teaspoon (5ml) of IchX. 3. Every 24 hours, change one-third of the tank water and repeat the dose. 4. You should continue daily treatment at least three days after your last sign of illness.

Pond Solutions IchX is more powerful than Aquarium Solutions IchX. Follow the same directions, but use a dose of 1 teaspoon (5 ml), per 50 gallons. Read our complete article for more information on how to identify and treat ich.

2. ParaCleanse

Fritz ParaCleanse can also be safely combined with Ich-X to preventively treat new fish in our retail shop. It can be used to treat both internal and external parasites such as:

– Tapeworms (e.g., skinny or wasting disease) – Gill and skin flukes (e.g., Gyrodactylus species) – Hole-in-the-head (HITH) disease (e.g., Hexamita and Spironucleus species)

ParaCleanse includes praziquantel, which is used to treat worms or flukes. Also, metronidazole is used to kill certain bacteria. It is safe to use on scaleless fish, fish fry and shrimp as well as snails, shrimp, and aquarium plant species. If you suspect your fish has one of these parasites, follow the manufacturer’s directions and do not treat with half doses (or else the medicine may not be effective).

1. Clean the aquarium, and get rid of any UV sterilizers and chemical filtration. 2. On Day 1, dose 1 packet of ParaCleanse per 10 gallons of water. 3. Dose 1 packet of ParaCleanse for every 10 gallons water on Day 3. 4. On Day 5, perform a 25% water change on the aquarium. 5. You should wait for your fish to gain weight and recover before giving them any other medications. To help them pass the dead worms, feed foods with fiber and roughage, such as spirulina brine shrimp, daphnia, algae wafers, and Repashy Soilent Green. 6. Follow Steps 1-4 for a 5-day repeat treatment after two weeks. (Eggs are not affected by the medicine, so we have to wait for the new worms to hatch out. This is why it takes stores 2 weeks to get rid of all internal parasites. 7. [Optional] Doing the 5-day treatment twice gets rid of the majority of parasites. You can make sure that your fish are healthy by waiting 2 weeks before repeating Steps 1 through 4.

Tapeworm eggs are not affected with most medications so we need to wait until new worms hatch before treating them. That is why we recommend redosing after 2 weeks once they have hatched.

ParaCleanse is not very harsh, so multiple treatments are generally safe for your fish. However, it can be a little expensive on the wallet, so try putting your fish in a smaller quarantine tank so that there is less water volume to dose.

Should the fish be medicated with food or water? It can be difficult to manage medicated fish food. Because they are sick, sick fish will often not eat as much or as often as normal. Also, it can be hard to monitor how much medicated food each fish is getting, so some fish may be consuming too much medicine while others are consuming too little. Meditated food may be an option if you only have one fish that is eating well. If you are treating multiple animals, we recommend medications that dissolve in the water and treat the whole tank so that we can ensure every animal gets the right concentration.

What is the treatment plan for the Quarantine Med Trio? After you have given your fish a 7-day soak with ParaCleanse and Ich-X, follow these instructions, starting at Step 5.

3. PraziPro

PraziPro has a higher concentration of praziquantel, so we recommend using it when ParaCleanse isn’t quite strong enough or if we’re seeing a problem with certain shrimp parasites like Vorticella and Scutalleria japonica.

PraziPro works in a similar way to ParaCleanse. It is safe for fish and invertebrates as well as plants and beneficial bacteria. PraziPro is used primarily to treat flatworms, tapeworms, flukes and turbellarians. These are the steps to use PraziPro:

1. Clean the aquarium and remove any chemical filtration and UV sterilizers. 2. Shake the bottle well and dose 1 teaspoon (5 ml) of PraziPro per 20 gallons of water. 3. Allow the medication to sit for seven days. You can repeat the dosage as often as you need, but not more than three times per day.

Wild-caught seafood often has a lot of parasites and may need to be treated three times in order to get rid of them all.

PraziPro is used to deworm puffers in our personal tanks. ParaCleanse is first treated for five days. Then, wait two weeks. Then we do a second 5-day treatment of ParaCleanse and then wait a month. As our final deworming step, we apply the PraziPro 7 day treatment.

4. CyroPro

Pond Solutions CyroPro was specifically formulated to deal with external parasites like anchor worms and fish lice (e.g. Argulus) Cyromazine, the active ingredient in the product, prevents crustaceans and parasitic insects from molting exoskeletons. This treatment is safe for fish, plants, snails, and insects. However, you might want to remove your shrimp, crab, and any other crustaceans before it can be used.

1. Make sure to water change the aquarium and pond. Also, get rid of all chemical filtration or UV sterilizers. 2. Give the CyroPro a good shake and 1 teaspoon (5 ml), per 50 gallons. 3. Change the water and repeat the treatment every 7 days for at least 21 uninterrupted days. If you are absent from a treatment day, restart the treatment.

External parasites such as fish lice (seen in the photo above) and anchorworms can be seen to the naked eye. They are commonly found on pond fish, like goldfish or koi.

The water changes that occur before CyroPro are used to restore dissolved oxygen, remove excess nutrients, and decrease the population of water-borne parasites.

5. Expel-P

Fritz Expel-P, a fast-acting, dewormer, is used to treat parasites like roundworms, planaria, nodular and hookworms. Infected fish may exhibit signs such as anemia, a swollen stomach, red worms leaking into the anus, rapid breathing, or loss of appetite.

The active ingredient is levamisole hydrochloride (HCl), which causes paralysis and death of the worms, but it will not harm your biological filtration, aquarium plants, invertebrates, or healthy fish.

Like Fritz ParaCleanse, multiple treatments are recommended to ensure that all the eggs have hatched and can be affected by the medication. Follow the instructions of your manufacturer and take the recommended dosage.

1. Clean the aquarium, and get rid of any UV sterilizers and chemical filtration. 2. One packet of ExpelP for every 10 gallons of water. 3. Do a 25% water exchange after 24 hours. Use an aquarium siphon to vacuum the substrate to get rid of any paralyzed or injured worms. 4. You can repeat the treatment once more worms have hatched after one week. 5. Continue the weekly treatments as needed until the worms have disappeared or the fish are regaining weight again.

Bonus: Aquarium Salt

Aquarium salt can be used to treat external parasites if you don’t have access to them. However, it is not as effective as internal parasites. The salt works by dehydrating the parasites to death before the fish (which have more mass and stored water) are affected. For complete instructions, see our full article on how to treat sick fish with salt.