Dr Tepper once mentioned (probably 15 years ago) about Plant Agglutinins and they are perhaps the best natural flocculant in a pond or fish tank. 
Just sticky proteins from plants that settle germs, micropollution and even parasites out of the water. The “idea” for the plant is that all these things are “organic material” which, if delivered to the roots of the plant on the bottom of the aquatic limnion, can function as food / fertilizer.
Plant agglutinins are proteins found in the cell walls of aquatic plants that act as a defense mechanism against predators. They are composed of two or more sugar molecules linked together and can bind to the surface of protozoan predators, forming a sticky coating that prevents them from feeding on fish and plants. Plant agglutinins can also bind to other particles in the water, such as bacteria and algae, and can help to keep the water clean. In addition, they can act as a signal molecule, helping to attract beneficial organisms such as bacteria that can help to break down organic matter and provide nutrients for the plant. The accumulation of plant agglutinins and beneficial bacteria is called “bio-film” and can compose the majority of an aquatic-system's nitrogen handling. Plant agglutinins are important for maintaining a healthy aquatic environment, as they help to keep the water clean and provide food for the plant.
This could explain why I have found over the years that barring viruses and other “winter stresses” that well-built and well-maintained Ecosystem / equilibrium natural ponds are healthier and easier to fix fish in, than purist-ponds with pressurized filtration, UV lights and guages.
A very good community tank population
This community would fit a 55 gallon tank. You would simply get less fish or use more filtration in order to have less water.

(3) “Gold Koi” Angelfish (Main event)

(1) Gold dojo when I see one

(3) Buenos Aires Tetras

(3) Zebra danios or (3-5) Pearl danios

(2) Albino Cory cats or similar

(3-5) Tiger barbs (Green if available)

(1) Plecostomus when algae appears 

(3-5) Serpae Tetra

(2) Ludwigia Plants

(1) Amazon Sword

PH Pills 










This is the BEST Filtration for Aquariums for Simplicity, Price and So Much More
I really love sponge filters because they're SO easy, easy to clean, easy to colonize, easy and cheap to buy.
Here's an article on the filtration method that's the SAFEST for breeder fish (won't suck up fish fry)
The filtration that does the most for water clarity the soonest. The longest cleaning interval and the lowest operating cost. (No electricity except for the air pump)
And it's the oldest filtration technology there is. Well maybe “undergravel filtration” is older.
Unlimited Vet-authored Pet Fish & Dog / Cat Pet Health Information is one of the most comprehensive online fish and pet health resources available today, dedicated to providing people with access to a wealth of knowledge and educational materials. It offers a variety of free resources, ranging from articles to to videos, downloads, ebooks, images, and audio clips. With so much to choose from, this web site can be overwhelming—but don’t fret! We’ve compiled a shortlist of the best resources has to offer, so you can make the most of your time browsing the site.

First and foremost, boasts an array of encyclopedia-style articles, with topics ranging from Ammonia and Water Quality to Zoonosis and Viruses. These articles are written in a casual, easy-to-follow tone of voice, making them perfect for any level of educational interest. In addition, the website features helpful videos and slideshows, as well as structured lessons outlining key concepts in various aquatic animal medicine subjects. Whether you’re looking to brush up on the fundamentals of fish care or learn the basics of koi virology, has you covered.’s database of helpful facts and care tips is another of its best and most interesting resources. Here, you can find things like fish care technology and facts about the best ways to keep fish and pets healthy, interesting tidbits about proper feeding of dogs, and even references to scientific discoveries and downloads. For the geek in all of us, this area of the website is invaluable.

Finally, the downloads available on can be especially helpful for those studying pet health. With downloads covering over 100 subjects, this site has something for everyone—whether you’re a first-time puppy owner, a seasoned dog trainer or a koi aficionado. 

All in all, is a fantastic online resource full of educational, fun, and interesting materials. Whether you’re a student, teacher, or just an avid explorer of knowledge, this website has something for you. So next time you’re looking for a useful source of information on pet health, look no further than

Fish Situation
Thank you for replying! If you let me, I have another question about the dosage and water changes of this treatment. 

My pond has 2900 gallons and here in Spain we don't have much water to do as much water changes. 
The medication product that I have is called “Tap Pond Professional Formalachite” which has a different dosage as the one you told me. (I inserted below two pictures; one about the product and the other from the dosage of it). 
What do you think It's the best for my case about this dosage treatment and water changes using this brand of medication in particular?
There's nothing on the Internet with an actual description of what's actually in that.
I wonder if you have a picture of the back of the bottle with the ingredients.
I would:
Do exactly as the label says and repeat in a week. Maybe they engineered it right. Maybe they put copper in it. :'(
Otherwise, if the problem still exists after a few days or at the end of that week, I'd dose every other day for three rounds.
See, there are certain life stages of certain parasites that are impervious to Formalin and Malachite.
For example eggs of Trematodes, and the encysted phase of Ich.
And for both, in warmer water, the life cycle is far shorter than a week.
But you have to give the manufacturer credit for their product testing so maybe it'll work by label instructions?
And if not, we can default to the every other day, safe but more aggressive way.
IMPORTANT:  If they put COPPER in that product, it would explain why you only add it once a week.
And it's blue like a chelated copper product.

Fish Situation
Hi Erik! I'm writting you beacuse I have some koi with a few red and clamped fins. I'm thinking about costia or trichodina but I dont have acces to a microscope to check it. I recently check my water parameters and are good. I'm from Spain and here It's springtime.
My pond its located near a forest and sometimes frogs came in so I supose maybe the parasites could came from that.
If you treat the pond with Formalin according to label instructions once a day x 4 days then skip a day, treat again, and skip a day and treat a sixth time –  it's unlikely that you will destroy MUCH of your beneficial bacteria.
If you perform a partial water change after each Formalin application it's even LESS likely that you'll do much harm to the beneficials.
It's mainly a “big deal” if the fish are crowded and the filtration / biological filtration is already strained.
If it's springtime, I suspect that the water will be cool enough for safe use of Formalin Malachite Green.
Let me know how it goes.
Fish Stress is caused by Fish Pathogens, Fish Parasites and FIsh Illness and Fish Infections are the natural outcome.

A.I. is generating a whole new wave of information to be re-purposed and re-posted in fish health web sites, by all kinds of people, most of whom don't even keep fish but want to populate a website to impress Google, and capture your Affiliate Ad dollar.

And in the process, will be giving out recycled, even incomplete or incorrect information about Fish Disease.

Aquarium health isn't going to be covered much better by these AI Generated resources. Fish Illness, same. People want to learn about fish symptoms but that's a problem because the fish symptoms of Ammonia poisoning are indistinguishable from the fish symptoms of PH crash.

Finally swinging around to Fish Treatment, the art of saving sick fish – which will be woefully lacking because current fish treatments are based on medications that are still, and actually available. Fish treatments like Clout, for example, are off the market but AI doesn't know this.

Fish Medicine is still rapidly developing but not much has changed in the fishes' lives. Water Quality is king.

Fish Parasites are almost-constantly a source of Fish Infection, because the parasites cause deterioration and stress in the fishes' skin, it's primary defense against disease. Fish infection is quick to take hold.

All of this including water quality are contributors to fish stress which is the primary if not-only cause of fish vulnerability to disease. Some would say that if the fish weren't stressed by handling, water quality or parasites, crowding or poor nutrition, they would be practically immune to disease.

A host of fish pathogens of many kinds including bacteria, viruses and fish parasites are ready to attack a vulnerable fish and all the fish medicine in the world won't save a fish that's still under Fish Stress.

1. Fish Disease is covered more thoroughly at or

2. Aquarium Health is covered more thoroughly at

3. Fish Illness is covered more thoroughly at

4. Fish Symptoms is covered more thoroughly at

5. Fish Treatment is covered more thoroughly at

6. Fish Medicine is covered more thoroughly at

7. Fish Parasites is covered more thoroughly at or

8. Fish Infection is covered more thoroughly at

9. Fish Stress is covered more thoroughly at or

10. Fish Pathogens are covered more thoroughly at or or even or

We'll cover all the following in the above web sites:
1. Fish Disease 2. Aquarium Health 3. Fish Illness 4. Fish Symptoms 5. Fish Treatment 6. Fish Medicine 7. Fish Parasites 8. Fish Infection 9. Fish Stress 10. Fish Pathogens
Where to find comprehensive and NOT A.I. generated errata on fish health issues:
<p>1. Fish Disease is covered more thoroughly at <a href=”“></a> or <a href=”“></a></p> <p>2. Aquarium Health is covered more thoroughly at <a href=”“></a></p> <p>3. Fish Illness is covered more thoroughly at <a href=”“></a></p> <p>4. Fish Symptoms is covered more thoroughly at <a href=”“></a></p> <p>5. Fish Treatment is covered more thoroughly at <a href=”“></a></p> <p>6. Fish Medicine is covered more thoroughly at <a href=”“></a></p> <p>7. Fish Parasites is covered more thoroughly at <a href=”“></a> or <a href=”“></a></p> <p>8. Fish Infection is covered more thoroughly at <a href=”“></a></p> <p>9. Fish Stress is covered more thoroughly at <a href=”“></a> or <a href=”“></a></p> <p>10. Fish Pathogens are covered more thoroughly at <a href=”“></a> or <a href=”“></a> or even <a href=”“></a> or <a href=”“></a></p>
Koi & Goldfish Infections
Bacterial infections are a common problem in Koi fish and can lead to serious health issues if not treated promptly. In this document, we will discuss the causes, diagnosis, pathogens, and treatment modalities available for bacterial infections in Koi.
Bacterial infections in Koi fish can be caused by a variety of factors, including poor water quality, overcrowding, and stress. Other common causes include injury, parasites, and viral infections that weaken the fish's immune system and make them more susceptible to bacterial infections.
The diagnosis of bacterial infections in Koi fish can be challenging as many bacterial infections share similar symptoms. However, there are some common signs to look out for, including:
– Loss of appetite
– Lethargy and sluggishness
– Redness, swelling, or ulceration of the skin or fins
– Excessive mucus production
– Erratic swimming behavior
– Abdominal swelling or bloating
– Difficulty breathing
If you notice any of these symptoms, it is important to seek veterinary care promptly to identify the cause and begin treatment.
Several bacterial species can cause infections in Koi fish, including:
– Aeromonas hydrophila
– Pseudomonas aeruginosa
– Edwardsiella tarda
– Vibrio species
– Streptococcus species
These bacteria can enter the fish's body through wounds, gills, or the digestive system and can cause a range of infections, including skin ulcers, fin rot, and internal infections.
Treatment Modalities:
The treatment of bacterial infections in Koi fish depends on the type of bacteria and the severity of the infection. Some common treatment modalities include:
1. Antibiotics: Antibiotics are the most common treatment for bacterial infections in Koi fish. The choice of antibiotic will depend on the type of bacteria and the severity of the infection. Antibiotics can be given orally, injected, or added to the water.
2. Salt baths: Salt baths are a natural and effective way to treat bacterial infections in Koi fish. Adding salt to the water can help reduce the bacterial load and promote healing.
3. Water quality management: Proper water quality management is crucial for the prevention and treatment of bacterial infections in Koi fish. This includes maintaining proper pH levels, temperature, and oxygenation, as well as performing regular water changes.
4. Wound care: If the bacterial infection is caused by an open wound, wound care is essential to prevent further infection. This includes cleaning the wound with an antiseptic solution and applying a topical antibiotic ointment.
In conclusion, bacterial infections are a common problem in Koi fish and can lead to serious health issues if not treated promptly. The key to preventing and treating bacterial infections in Koi fish is proper water quality management, prompt diagnosis, and appropriate treatment modalities. If you suspect your Koi fish may have a bacterial infection, seek veterinary care immediately.

My Favorite Seminar of the Year by Dr Erik Johnson
Special thanks to Garden State Koi and their amazing staff, Jesse Blitz in particular but the entire team is amazing. I mean, capable and nice and fun –  aka amazing. They've had a wintertime educational workshop 'most years' and they've included me in these a lot –  I usually go up and present some seminars on fish health, pond stuff, and then quite often, the Wet Lab where folks can see parasites under the microscope, on videos, learn about them, and their diagnosis and treatment.
It's all part of Tom Smith (Owner and President) of the company vision for educated customers, of any kind. Librarian, Fireman, resident, Installer –  everyone does better with more information.
They're in Warwick New York and they've kind of gotten to be this big, one-stop shop and they also service / supply contractors in the pond business. And they do it well.
I went up in March of this year. I gave a presentation and a wet lab and it was wonderful. I'll give you some information about Garden State Koi and if you wanna get into the next Wet Lab and seminar weekend –  reach out to them and they'll sign you up!  I bet if you ask 'em nicely they'll let you have a copy of the presentation I gave. It's only 50+ pages thick in color hahaha.

Garden State Koi Pond & Waterfall Design Center is a pond supply store located in Warwick, New York. They have been in business for over 25 years and offer a wide variety of products and services for pond owners, including:

  • Pond design and installation
  • Pond maintenance and repairs
  • Pond supplies, such as liners, filters, pumps, and plants
  • Koi and other pond fish
  • Educational resources about pond care

Garden State Koi is a Master Pond Construction company and distributor of AquascapePRO Pond Products. They are also certified by the National Koi Association.

The store is located at 657 Route 94 in Warwick, New York. They are open from 9am to 5pm Monday through Saturday, and from 9am to 7pm on Wednesday.

Here are some additional details about Garden State Koi:

If you are looking for a pond supply store in Warwick, New York, Garden State Koi is a great option. They offer a wide variety of products and services, and their team of experienced professionals can help you with all of your pond needs.

657 Rt. 94, Warwick, NY 10990 / 845.651.4100 /