Chloroquine Phosphate – It’s Not A COVID Cure Damnit 😆!

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I’m really frustrated and tired of the news about Chloroquine Phosphate. There is so much bad information about Chloroquine Phosphate it has gotten to the point where it’s affecting my business. I’ve been in the marine fish keeping industry for over 20 years. I’ve used this substance on marine fish in quarantine for ages. I’ve been quietly speaking its praises to my fellow hobby club and group members. It’s been my secret weapon for years in battling the most deadly marine fish diseases over the years.

It is a sad day for me today. Today, I had to take down my Choloroquine Phosphate product from my store. I can no longer sell it, and it all started with a generic announcement that became a bad news story. I tried to dispense with the myth that it was a cure for COVID. I was even on the news to talk about it. I was verbally abused by prospective customers through live chat and the phone because I refused to sell the product to them after they openly admitted to me that they were planning to use it for human consumption. I was threatened 3 times by my merchant provider to take off my product from my store or face losing my merchant account and getting my site completely shut down.

Today enough is enough, the product is getting de-listed. But I’m not simply going away. I redirected my old product to this page to educate folks on what Choloquine Phosphate REALLY is, why it’s an amazing product FOR FISH, and my story as to why I ultimately ended up pulling it from my store. So sit down, relax, and enjoy my story. It’s going to be a doozy!

What Is It?

Chloroquine Phosphate, is an antiprotozoal drug used by marine and aquarium hobbyists to treat fish suffering from Cryptocaryon (Marine Ich), Marine Velvet, Brooke, and Uroema.

Chloroquine Phosphate is so well regarded in the marine hobby that it was covered by Advanced Aquarist as a wonder drug. It became the drug of choice for many public aquariums including the Georgia Aquarium. It has been widely used by hobbyists in the early days of the marine aquarium hobby and used in the aquaculture industry since the 70s and 80s.

It is typically unavailable to the majority of the reefing community due to it normally being available through a Veterinarian via a prescription. As you can imagine, it can be very difficult to obtain a prescription for this wonderful medication as there are not many fish vets available who know about the medication or would be willing to prescribe it.

How I Got Started With It

I started the reefing hobby in the late 90s and was a member of the local aquarium club in my area at the time. I was introduced to the process of quarantining marine fish after having several issues with Marine Velvet. Chloroquine Phosphate became an amazing medication. The biggest advantage to it versus copper was that it would work with zero ramp up. This was a huge development because Marine Velvet and Brooke work very quickly against a marine fish. Within 24-48 hours, most fish will die from getting overwhelmed from these diseases.

Chloroquine Phosphate was simply amazing. I never lost a battle with Marine Velvet using this medication. Back then, it was easy to obtain this medication without a prescription because there was this amazing product from Aquatronics called Marex. Marex had just enough pure Cholorquine Phosphate to be effective and also was inexpensive. It was also available without a vet’s prescription. It was my go to until Aquatronics went out of business in the early 2000s.

I have been a promoter of this medication for many years, so much that I have a blog post on how to quarantine fish that details how to use the product. You can see my video below.

How I Got Started With Selling 

After Aquatonics went out of business, I was frustrated on how I couldn’t get this medication. The vets around me had no clue what I was talking about and I was hearing more and more that vets weren’t prescribing it anymore. You had to go to a vet who either specialized in marine fish or koi ponds to get the medication. There simply weren’t that many vets around who specialized in fish. So where could I get this medication so I could have a chance against the deadly 3 (Marine Velvet, Brooke, Uroema)?

This is when I found out about Fish Pharmacies. They sold medications to public aquariums and aquaculture facilities who needed the medication to cure their livestock. I was amazed that I could get this medication from them, but the amount they sell you in bulk was quite a lot. You would have to purchase a kilogram at a time while most marine fish keepers would maybe need 50-100 grams max in their medication drawers to get what they need.

I had my stash of Cholorquine Phosphate for my incoming fish for my reef tank. I heard so much on the reefing forums of people racking their brains trying to fight off Marine Velvet with Seachem Copper. It was sad to see so many people fail. Copper is tricky to use while Cholorquine was a one-time medication then you just replace with more medication as you change water. Super easy!

As I heard more and more about people losing fish to marine velvet, I started to sell Cholorquine Phosphate on this site. I had a certificate of analysis showing 99.9% purity of the product. I was the only seller on the web that had such a certificate at the time.

Chloroquine Phosphate Certificate of Analysis

As the availability of Cholorquine Phosphate became more scarce, I started to obtain the medication through labs that would sell to universities. Since I had a commercial license, I was able to procure the product. I was rocking and rolling selling to customers who were saving marine fish life everyday with this wonder fish medication. It was really rewarding getting the emails thanking me for selling them the medication.

COVID-19 And “Chloroquine”

COVID-19 has been a mess for everyone. My own business was affected not just with the general downturn of the economy, but the affect on prices on livestock in the marine hobby. Price for fish and corals skyrocketed 2 -3 x times their usual price as imports closed up and supply became restricted. My fish medication product also became part of the news cycle when the President of the US announced that the U.S. Food and Drug Administration (FDA) had approved the use of hydroxychloroquine against COVID-19.

Unfortunately, the President and most of the media shortened the name of the drug to Chloroquine. In came all the new articles talking about Chloroquine and how it would aid in the fight against COVID-19. Search results exploded for everything Chloroquine. Everyone wanted their hands on it.

It became very easy to confuse the abbreviation Chloroquine with Chloroquine Phosphate. The price of this well loved fish medication exploded overnight. Once an affordable medication, Chloroquine Phosphate was all of a sudden selling for over $400 for only 10 grams. People wanted to use it for human consumption.

I started getting messaged on my live chat from people asking me if they could use this medication on humans. I told them that it is a fish medication and it is not for human consumption. I got several angry messages in my live chat when I refused to sell them batches of the medication as they openly said they were going to use it on loved ones affected by the virus.

My Interview With NBC News

This was starting to get crazy. I was contacted by a BBC journalist who wanted to talk about the product I sold in my store. They had told me that a man had died ingesting this medication in Arizona. I was horrified and concerned for the public health. I was also cringing when I read the article and it mentioned that the product was a fish tank cleaner (it’s a medication not a fish tank cleaner). They asked me if I was interested in being interviewed on TV about my experience. I was happy to do so. I wanted to dispel the myths about this medication.  I spent about 2 hours in meetings with BBC and then my interview was displayed on NBC News.

I felt much better getting the word out. I had chosen to place the medication product as out of stock in my store when I first heard of the FDA announcement. I had a feeling that it would get confused. I was planning to keep it out of stock until this COVID-19 mess was behind us. I wasn’t ready about what was going to happen next…

Shopify Threatens To Shut Down My Store

A couple of weeks passed since my interview with NBC. I was getting ramped up on some new content I was writing and went to check my email. I got a notice from Shopify that my product was removed from my store. The product was marked as high risk due to it being related to the Coronavirus. They sent me a notice stating that there was a risk that I was price gouging and had to provide proof that this wasn’t the case. They wanted to me to provide proof of my historical price of the product and also prove that a major retailer sold the product near the price I sold mine for. I was surprised that my store was threatened to be shut down thinking I was price gouging. I never increased my prices and had positive reviews for my product. I explained myself to Shopify and got everything lifted.

A few days later after my product went offline, it was pulled again for the same reason. I responded to the risk department with all my past communication. I took it further and gave them the interview link to my talk with NBCNews. They apologized and I was listed again. I was told all was good after that.

Shopify Labels My Product As A Pharmaceutical 

A few weeks past. My site was getting a curiously high amount of traffic since my interview. Likely due to folks landing on my product page and seeing my product in the search results. Things were looking pretty good for me. I was having a great month despite the lockdown orders and my biggest challenge was supply chain restrictions. I woke up one morning and received another letter from Shopify.

This letter was a bit different. I was having my payments held because Shopify’s risk department had labeled my product a Pharmaceutical. Looking at the terms of service, the fish medication product I sold was being placed under regulated or illegal products or services. This labeled my product as no different than cannabis dispensaries, tobacco sales, age restricted goods or services, weapons, etc. I was floored.

I tried to explain the situation to the risk department. They said my best course of action would be to find another merchant supplier who would be willing to work with my product. This put me in a tough spot. I had my payments withheld during this time and no merchant services provider that was referred to me was answering emails or picking up the phone due to staff reductions related to COVID-19. I was a rock in a hard place.

Since I couldn’t get anyone on the phone and there was risk that this could happen again, I decided to remove my product permanently from my store. I felt bad for my past customers who came to rely on this product to save their sick fish. There wasn’t much else I could do.

What It Isn’t

Now that you know the story and why I won’t relist my product. Let’s talk about what Choloroquine Phosphate isn’t.

It Is Not Fish Tank Cleaner

I have no idea where the news got this information from. It is not used to clean fish tanks. While it does have anti-algae properties, its primary purpose is as a antiprotozoal medication. I said this in my talks with BBC, but for some reason it never showed up in the news article or the interview.

It Is Not A Medication for COVID-19

It was hydroxychloroquine that was approved by the U.S. Food and Drug Administration. They are two completely different drugs. Cholorquine Phosphate is used for humans to treat malaria. The brand name for the drug is called Aralen. Is not the same thing that I sold. My product was the substance in it’s purest form. The drug designed for humans is not pure Choloroquine Phosphate. This is likely why that poor man in Arizona died ingesting it. He had likely overdosed on the drug.

The Food and Drug Administration (FDA) Warns Against Using It

On March 27, 2020, the FDA sent an public health letter to stakeholders warning to not use use Chloroquine Phosphate intended for fish as treatment for COVID-19 in humans. The FDA closed the letter with the following:

People should not take any form of chloroquine unless it has been prescribed by a licensed public health care provider and is obtained through a legitimate source.

You can find the full letter here. Amazingly enough, the letter itself did not receive much news coverage.

What It Is

Let’s talk about what this medication is for fish. It is

  • Superior to and more gentle on fish than copper
  • A 10 Gram bottle treats 250 gallons at a 40mg/gallon dosage
  • Chloroquine Phophate (CP) is the drug of choice for diseases like Ich (Cryptocaryon irritans), Marine Velvet Disease (Amyloodinium), Brooklynella hostilis, & Uronema marinum
  • One time medication – only replace medication in the event of a water change
  • Chloroquine Phosphate acts as an algaecide eliminating algae in the quarantine tank.

How to Use It On Fish

Since my product got taken down, I’m going to use the how to use instructions that were on my product page for anyone who attempts to use this on their fish.

  • For Quarantine (Prophylactic) Treatment – Typical dosage for quarantine is 40mg/Gallon
  • When dosing Chloroquine Phosphate, treat water with a pre-dissolved solution using a cup of tank water
  • For Ich – 30 day active treatment
  • For Velvet – 14 day active treatment
  • For active infection – up to 60mg/gallon
  • For Uroema – up to 80mg/gallon
  • Highly recommended that you use a digital scale to measure your dosage to ensure accuracy
  • Keep medication in a cool, dark, and dry pace. Chloroquine Phosphate is heat and light sensitive
  • If a water change is performed, Chloroquine Phosphate will need to be re-dosed for the amount of water changed. You do not need to dose Chloroquine for top off water.

Additional Warnings about Using It On Fish

Here are the additional notes and warnings that were on my product page that I’m displaying for anyone looking into this medication.

  • Not reef safe – Chloroquine Phosphate is meant to be used in a quarantine for prophylactic treatment or in a hospital tank for active infections.
  • No one ships Chloroquine Phosphate next day If you have an infected fish and you need treatment now I highly recommended going to your LFS and obtaining Copper. Most of the diseases Chloroquine phosphate treats are extremely deadly and can kill a fish overnight

Closing Thoughts

I’m sad to no longer offering this life saving treatment for what I call the deadly 3 marine fish diseases. Hopefully COVID-19 gets past us sooner than later and we can all return to normal. I hope clinical trials go well with the vaccine being developed. Maybe we will see Chloroquine Phosphate offered again as a treatment for marine fish diseases in the future. Right now, the supply chain is on hold due to concerns that people will use it for human consumption. Stay safe. My thoughts are with you all. We will all come out of this stronger. Take care and thank you for reading.


  1. If they were “concerned about safety” there were numerous chances to exhibit that notion over the past two years. This aint about a germ or safety.

  2. Good afternoon.
    I have thoroughly enjoyed reading your blog.
    I have an unexpected outbreak of velvet in my aquarium and it has progressively gotten worse.
    I am treating with Ich-x, but after a week, it does not appear to have gotten any better.
    Any suggestions on how to get a small amount of CP? I thought that since it has been a while since the hydroxychlorquine hype has passed that maybe you have an update on getting some?
    Thanks for any information!

    • Hi Margo,

      Unfortunately, it still is difficult to obtain CP from the sources I used to get them from. Vets are still cautious and supplies are still limited. The only major source I’ve found reliable is National Fish Pharmacy, but they are do go out of stock quickly. Copper (I favor Copper Power, but make sure it works for your fish species) is the main fighter of the disease now with the limited access of CP.

  3. Getting Ready to by a Lion Fish and will need this for QT. Any idea when it will be back in stock. i don’t know of any other reputable source

    • Hi Ethan,

      Unfortunately I don’t :’-(. The pandemic messed up the supply chain and no one wants to sell it right now due to the misinformation. I’m thinking maybe late 2021. CP should not be used on a Lionfish though.

      • Hi Mark,

        Sorry about the situation you were placed in.

        I just spoke to NFP, and it seems they have QP AT AROUND 98% pure? Are you sure that it’s no longer available, because that wasn’t the case as of earlier today-that is, unless I’m confusing something?

      • NFP was one of the sources where you can obtain CP. They get it from India. Humblefish has used it before. He hasn’t reported any issues so I would say it’s safe to get that. I stopped carrying it after all the drama I dealt with. It wasn’t worth it anymore.

  4. Does CP lose potency when there is an active biofilter? I have moved a seeded sponge from my dt and dosed biospira. Should I be concerned?

    • It’s only a concern if you run a permanent Quarantine tank. If you take it down often – it shouldn’t be a problem. I usually deal with expensive fish I usually sterilize after a batch of fish that I quarantine.

    • I would not. CP has only been field tested and studied in marine fish. I am not certain of the application for freshwater and would avoid using unless we start hearing of public aquariums using it. I became a fan of CP after learning how widespread its usage was at the Georgia Aquarium.

  5. Sorry for your troubles; seems the world has really lost its mind over the last few weeks. Seems there no end to the damage uniformed people can do.

  6. I had a velvet outbreak RIGHT before the pandemic happened, and was thankful that I had a great rapport with my vet so he prescribed me CP, and then I bought some later on Ebay as backup. Now that my fishies are looking good and healthy, I want to start getting some more livestock. However I refuse to put anything in my display tank that hasn’t gone through CP treatment even prophylacticly. It’s just a shame because now I don’t know what I’ll do if I ever have a sick fish again, or want to buy more because I can’t find CP anywhere…..

  7. I need some CP how can i buy it from you and thanks for the videos also how do u kjow hiw much to use after a water change thank u again


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