Gerald Bassleer Interview

Wellcome mr.Bassleer to Diskusari  community  First Croatian Discus Club

Can You introduce yourself?


Gerald Bassleer (*1954, Belgium):Fish pathobioligist since 1977 working in the ornamental aquarium industry in Belgium, USA, The Netherlands, Germany; currently active as „flying fish doctor“ providing internatioanl service for several exporters & importers of ornamental  fish. Author of 5 books on ‘fish diseases’ and our company Bassleer Biofish (BE) produces  Dr. Bassleer Biofish Food (= a functional food to promote health of fish, with prevention or help in control  of fish diseases); Website



You work at Aquarium Munster(=AM) one of the most popular firm which produce professional medications for fishes ?

I work for AM as consultant and as supplier;Bassleer Biofish is the producer of Dr. Bassleer Biofish Food and we supply AM

Aquarium Munster also produce  fish feed, how we can see many ingredients of this feeds come from nature,did exsist some special reason for that?

The use of our food prevents many diseases, it prevents the use of many medications, gives more health and less losses …and more profits for the exporters, importers and breeders: we started to develop our special fish food in 1996 when we had our own wholesaler & testing facility of ornamental fish in Belgium; we learned a lot from people living close to nature.

If I remember good before two years Aquarium Munster put on market some medicated feeds with natural  based medications for spironucleus (hexamita) and nematodes PUMPKIN and  LAPACHO did they work when fishes are sick but still eating or just we need to use it like preventive?








We do not call our fish food ‘medicated’ food…but are food is a functional food that helps the fish to fight infections and stimulates faster repair!
Dr. Bassleer Biofish Food LAPACHO: helps in control Spironucleus(ex-Hexamita) and repairs the damage to gut & lateral line erosion (with garlic &chlorella & probiotica Pediococcus)= we recommend to use as prevention or as treatment (to obtain results: feed only this Biofish Food lapacho during 10 days and NO other food)
Dr. Bassleer Biofish Food PUMPKIN: helps in the control of worms in the gut: to be fed during quarantaine or infection.


Biofish food ACAI is one of the newest product can You discribe itt a little better?

We have learned the great help of açai in the Amazon: fishermen did collect the strongest and most colorfull fish in areas where fruit berries açai dropped into the water: the fish love it! It is a kind of ‘Red Bull’ that gives ‘power & color’ to the fish; try to stimulate the natural color pattern ‘in the natural way’ and great for breeding pairs!



One of the new food on the market is MATRINE this feed repels a parasites like ich from fish,how long we need to use it to get rid the ich from aquarium?

Dr. Bassleer Biofish Food Matrine is made for several reasons: 1. Prevention for fish susceptable to ICH (for example the freswhater Clown loach or the marine fish P. Hepatus Dory) 2. During infection in combination with a medication 3. For Reef aquaria where hardly no medication can be used
The MATRINE, when accumulated in the mucus of the fish (after sufficiant food uptake) it works like a kind of repellant so the parasite does not like to attack or does not like to remain on the skin or gills of the fish!


The medication (like Faunamor) kills the (baby) parasites, the Dr. Bassleer Biofish Food matrine helps the fish to fight off= this means faster & better results when there is an ICH infection

(note: during ICH-infection do not feed other food and follow the Dr. Bassleer anti-ICH Method: PDF




HERBAL food in description i found a sentence „Skinny fish gain quickly more weight“ that supposed it good to use after  some disease like nematodes or spironucleus when fishes are loose a weight?



The Dr. Bassleer Biofish Food herbal contains 4 different herbs (Thyme, Minth, Mugwort, Chickweed) that helps in repair with good help as ‘desinfectant’ & assist in the control internal bacterial & viral infections): lately often used for Fancy Goldfish that suffer from Swimmbladder disorder.





GSE/MORINGAhelps the fish to fight internal bacterial infections,




GARLIC has multiple control action to help the fish to fight off internal parasitic and bacterial infection AND gives the food a great attraction for the fish (the fish „smells it) ,








REGULAR is our BASIC food for every day: all our types of food are based on Regular where we add ‘supplements= phytobiotics’ like grapefruit seed extracts, Chlorella algae, garlic, etc.

Many of the foods contains a big value of proteins  from  47 and more %,also contains probiotic bacteria,and free of artificial colors,did this make this feeds unique?

The use of good ingredients (such as wild marine fish: herring, mackerel and whiting all collected in a sustainable method according IFFO-standards) and extra herbal, vitamines, minerals, probiotics Pediococcus acidilactici ,etc. All produced as granulate food with optrimal veterinaty control = Makes it a unique blend for most (99%) of our ornamental fish


Also one interested thing is,all food are granulated form.what is a reason for that?

We prefer granulated food:

1. Production process guarantees best preservation of valuable ingredients;

2. Food needs to sinck to all ‘layers’ in the aquarium (only very few fish eat at surface and our smallest food baby or medium floates longer time as service and sinks much slower= good for many small fish);

3. Our food is maximal taken up by the digestive track of the fish: very little waste& very little pollution of the aquarium water;

4. We supply 6 different sizes of granulates for diffrent sizes of fish-mouth;

5. Granulates are usually well dispersed and prevents fights & aggression between fish;

6. Granulates are sasy to coat our natural phytobiotics/nutricaments, after production & heating process so the necessary, beneficial ingredients of our phytobiotics are preserved.(For example: garlic prepared in flake food looses all activity of the ingredient allicine since these molecules break down at 60°C);

7. Our granulates remain as real dense food particles for 12+ hours and do not break open so the fish has plenty of time to find their food in good condition and avoiding pollution of the water.


Aquarium Munster foods present also at Brasil in one of the biggest exporter of wild discus fishes Hudson Crizanto.Discus fishes (especially wild collected) are very hard to accept a new kind of foods especially flakes and granulate which is the best way to addopt them on new food in diet?

Hudson is a great expert in Discus fish! He knows that fish, and especially Discus, are like little children…they prefer the sausage and not the fish or vegetables….sometimes the Discus need some time to adjust and when the Discus has difficulty to change over: try our Dr. Bassleer Biofish Food cavar (our nr.1 in quality & attraction for fish); Try not to feed other food when you want to try ours. But in many cases Discus (like the Wild ones from Hudson in Brazil) love our food immediately!

Which feeds from Aquarium Munster You can reccomend for feeding discus fishes?

We recommend for Discus: Dr. Bassleer Biofish Food Regular, Açai, Garlic, Pumkin and Lapacho (and soon a new one ‘FUCO’  to help control the terrible bacterial Columnaris infection.


Many hobby keepers are not have microscope,they when try to get help describe only white feces discus not eating,how they can recognize difference between spironucleus and nematodes ?

Sorry to say but only with the help of the microscope you can make a correct diagnosis! White feaces is a symptom (sign) not a disease….and can be caused by many different factors (also cause by contaminated froozen or fresh fish food that contains too many bad bacteria).


Can You tell us something about medications and a resistency ?Did a fish diseases after a years of use same medications  possible to make resistency?If yes did exist some alternative ways to cure our fishes?

Yes, parasites or bacteria can become resistant after long time use (especially when used too much as prevention and not as treatment, or when the medication is kept too long in the aquarium: follow the directions !): alternative way: use the medication correctly: correct dosage, correct period of treatment; Also use our kind of functional food that helps the fish on a ‘natural way’ to fight off  infections. Especially strengthening the immune-system is very important!With the help of our probiotic Pediococcus acidilactici in all our Biofish Food we improve the microflora of the gut (=a very important defense against infections) and also with our prebiotica Betaglucanss (yeast extracts) in our Dr. Bassleer Biofish Food forte and Dr. Bassleer Biofish Food Professional Treat(also with garlic & herbs) we can help the defense (immune) system of the fish.

In some cases you might need to switch to another kind of medication.

Most of the problems occur beause people do not make a correct diagnose= so they use a wrong medication; or hobbyist ‘over-dose’ because they believe it will work better/faster which is in-correct (over-dosage causes damage to the fish and in many cases parasites survive better with over-dosage, especially with skin and gill flukes is scientifical proven).


One of the biggest questions for all discus keepers  is a discus plague,how to cure it or how we can avoid that?Did You make some research and find some solution if happens how to get rid that problem?

Interesting question! I published in my book„The new illustrated guide to fish diseases’“a chapter on this subject! Untill now no scientific study has been published! All different reports/publications on different cases of ‘The Plague’ has shown different problems!

For me:

  1. Each case can be different;
  2. usually it is the introduction of a discus (or its water) to another discus from a different origin (usually different country/continent: like Asian Discus could affect European Discus);
  3. Each Discus has a specific immunity or resistance against specific diseases= when they come in contact with something they have never seen they might get infected & diseased;
  4. In most cases I notice a kind of allergic reaction that looks similar to asthma in people: the fish has come in contact with strange substances (pheromones?) that he doesn’t know to handle;
  5. In some cases it could bacterial and/or viral infection;
  6. We see mostly, after THE PLAGUE, secondary bacterial infections or secondary parasitic infections (like Chilodonella, Ichthyobodo, Spironucleus), etc.
  7. I recommend; not to mix species(&water) from different origin and when there is ‘The Plague” to treat with lots of water changes and treating the secondary infections (anti-bacterial & anti-parasitic); at the same strengthen the immune system of the fish with Dr. Bassleer Biofish Food forte


Beside this questions do You have tell us something we didnt ask but You think is it important?

Too many hobbyist ‘guess’ the disease and make incorrect diagnosis & treatment; the internet is terrible in providing a very poor fish diagnostic service= when I see what kind of diagnosis are made by just seeing a photograph of the fish, I feel very sorry for the mis-treatment of the fish (=cruelty of the animal!); try to be in touch with someone that know how to use the microscopen for a proper examination of the diseased fish (or its excrements, or mucus from skin & gills).


Mr. Bassleer thank You to accept this interiew we wish you all the best in your future work.