"Cross contamination"?

[illumnae]

I'm not exactly a beginner, but I have not kept domestic discus in over 15 years, and last kept wild discus probably 10 years ago. In the interim though I have kept wild caught South American cichlids, went into reefing for a number of years and most recently kept Tanganyikan cichlids for the past 2 years. However as far as the latest trends in discus keeping go, I'm probably as good as a beginner and that's why I am posting here.

I recently had to empty out my custom 600 gallon (7 x 3 x 4 ft) aquarium as it suffered a fault and had to be repaired. After getting the repairs done, I decided that I wanted to go back to keeping discus again - my first love in fishkeeping. The plan is for a hardscape heavy "flooded forest" theme planted tank with hardy plants like amazon swords, crypts and epiphytes. I do not enjoy sterile bare tanks. Unfortunately for me, when doing some research for my tank by speaking with discus breeders, discus importers (from overseas breeders) and Facebook groups, it seems that the latest buzzword is "cross contamination" and I'm being told that at the very least I need to keep my tank in absolutely sterile conditions and more extensively I am only able to purchase 1 batch of discus from 1 breeder and never be able to add any other fish (discus or otherwise) without a high risk of tank wipeout due to cross contamination. Some tell me that the very bare minimum is to employ the "hero fish" method after completing quarantine but be prepared that even so, the risk of tank wipeout is still high if I am unlucky. Basically I'm being told that unless I intend to have a sterile bare tank, don't bother keeping discus.

Now don't get me wrong, I'm all for proper quarantine procedures. I've kept enough highly sensitive marine and freshwater fish to know better, including true blackwater species like altum angels and uaru fernandezyepezi which usually arrive with barely any immunity system developed due to most pathogens being unable to survive in the low pH blackwater that they originate from. My usual quarantine process includes prophylactic treatment with metronidazole, praziquantel and levimasole for internal parasites and Waterlife Parazin for external parasites. I use antibiotics as needed if the fish displays symptoms of bacterial infections, or prophylactically in the case of blackwater species to aid in developing their immune systems (of course a different process is used for marine fish). My quarantine tanks are disinfected with a bleach compound between batches of fish (I'm considering switching to pp for cost reasons). My main tank has been disinfected with hydrogen peroxide after being emptied out (I can't use bleach or pp in the main tank due to my 3d background not being able to tolerate both chemicals). I also run a uv at sterilization levels 24/7 to reduce pathogenic levels (yes I know it doesn't eliminate them). I have never employed the "hero fish" method and I don't intend to in this case as the combination of a 4ft tall tank, heavy hardscape and a 3d background makes it almost impossible for me to catch healthy fish from the tank without tearing it down first.

The aforementioned safeguards I have in place have been sufficient for me to keep highly sensitive and delicate fish species as mentioned above, including long ago when I used to keep domestic discus in a planted tank (discus acquired from different breeders) and wild discus in both planted and biotope style tanks. I know that some people may say that I've just been lucky, but it's hard to believe that it's just luck when the practice has been sustained for almost 20 years.

For full disclosure, my plan is to either keep wild tefe green discus, or a mix of albino red covers and albino panthera (that's another thing I've been told, that I need to keep albino domestic discus only as non-albinos will turn black or pepper in a planted tank). In both cases, the fish will come from the same importer but may come from different sources (for the wild discus) or breeders (for the domestic discus). I will definitely want tankmates with the discus like tetras and cories, and I am likely to add more fish in the future to replace unplanned deaths or just because another fish caught my fancy. All fish whether discus or otherwise will go through the quarantine process I described above. To me, this just seems to be normal fishkeeping wants and are not unrealistic or unreasonable.

I just wanted to check in on whether my plan is really as impossible and doomed for disaster as I have been told? Have discus really developed into such weak and zero immunity animals over the past 15 years? or is this a case of exaggeration creating misinformation being spread over the internet? Aside from the "hero fish" method are there any other recent best practices that I can add on to my quarantine process - for example I was advised to add a bath using Discusfood Discus Protector as the final step just before any fish goes into the tank after completing my usual quarantine process.

[brewmaster15]

Theres really a ton of misinformation you have received. Ignorance runs wild on social media.

I think you will be fine. You sound well experienced and the fact that you are questioning what you are being told is a good sign.


The hero fish is your best chance of detecting a problem but a well cycled sponge from your established tank and some tank water will be a good subsitute given you can't do a hero fish.

You can mix stock from suppliers after a lengthy QT... I would suggest 6-8 weeks. It is easier to get all discus from same source at same time ..but most people dont for various reasons. Theres always a chance fish will crash when.mixed...but a long quarantine goes a long way to preventing that.

Have discus really developed into such weak and zero immunity animals over the past 15 years?

absolutely not but more countries are breeding them and shipping globally. Different water means different organisms,bacterias and virus. Theres also a greater chance of pathogenic bacteria that are harder to treat as antibiotics in aquaculture is a huge problem.

I've been told, that I need to keep albino domestic discus only as non-albinos will turn black or pepper in a planted tank)

false.

[jeep]

Congratulations on questioning what you've "been told", lol... That's why this forum exists!

Discus are not weak. The care they receive is what determines your success. Heavily planted tanks aren't the best environment but success can be achieved as long as you understand their requirements, basically clean water and a reduced bioload.

As far as cross contamination goes, if you perform a strict quarantine you will more than likely be ok. This is true with all fish, but discus can be more susceptible to CC related bacterial issue because of their slime coat.

You've been a member here since 2007 so you do have at the very least a basic understanding on how to keep discus. Work that to your advantage and stay away from other internet sources, and Facebook in particular.

Here's a couple of links for reference -

QT - https://forum.simplydiscus.com/showt...tine-Procedure

Bioload and water quality - https://forum.simplydiscus.com/showt...-Are-Important

[illumnae]

Thank you both for your quick responses and encouragement! I found it strange that discus keeping would have become near impossible in the years I was away from the hobby, and what I was told just didn't resonate well with my experiences with other sensitive fish.

Just one question about the alternative to the hero fish method - are we trying to prevent the new fish from infecting the established fish or vice versa? Should I be mixing water from the main tank into the quarantine tank, or from the quarantine tank into the main tank?

I'm very much looking forward to setting up this tank and returning to keep the fish that I regard as my first love since i was a kid. I'm still trying to source for a nice large group of Tefe greens, but the likelihood of that happening has diminished over the past 2 weeks - it seems that Aquarium Glaser has sold out on the full spotted greens that I was eyeing. My importer is now trying to source for them from Colombia before an export ban kicks in (Brazil has ceased exports for 2 months already due to a strike). If unsuccessful then I will try to obtain a mix of albino red covers and either golden panthera or albino panthera, if the discus blackening/peppering isn't going to be an issue. The bright reds would look really good against the green of the plants.

[brewmaster15]

Just one question about the alternative to the hero fish method - are we trying to prevent the new fish from infecting the established fish or vice versa? Should I be mixing water from the main tank into the quarantine tank, or from the quarantine tank into the main tank?

This is where I said the hero fish is best. If you take the hero fish and add it to the new fish in qt you get more info.. if the hero dies/gets sick its a problem.. if the quarantine fish die/get sick its a problem.

If you use the media and water from the existing tank you only get info on whether the quarantine fish get sick... but its far better than just throwing them together in the display and hoping for the best. The key is that 6-8 week qt... by then most people will not have an issue mixing stock

If unsuccessful then I will try to obtain a mix of albino red covers and either golden panthera or albino panthera, if the discus blackening/peppering isn't going to be an issue.

neither of these lines are pigeon based..therefore they do not have pepper .. only pigeon based strains have pepper.

[illumnae]

Thank you very much! Hero fish option is unavailable to me as explained above but I'm definitely sticking to the 6-8 week quarantine using the process I described above

[brewmaster15]

Look forward to watching the journey..Welcome back!

[illumnae]

Thank you! I'll start a thread in the planted or tank journal section

[brewmaster15]

Awesome!

[illumnae]

Would this be a correct way to do the "hero fish" trial:

I have a group of fish in quarantine since mid January. Way over 6 weeks and they've completed prophylactic deworming. They're dwarf cichlids so pretty hardy. I've also got a batch of discus separately quarantined (coming 3 weeks) and about to complete prophylactic deworming in a few days. Once the discus have completed their deworming, can I introduce the dwarf cichlids into the discus quarantine tank for a week to confirm that there's no cross contamination before putting the dwarf cichlids into the main display tank?

[brewmaster15]

Whats in the display tank?

[illumnae]

Whats in the display tank?

At the moment nothing. These will be the first fish in. Everything else is being quarantined for the 6 week duration, including the discus.

[brewmaster15]

Would this be a correct way to do the "hero fish" trial:

I have a group of fish in quarantine since mid January. Way over 6 weeks and they've completed prophylactic deworming. They're dwarf cichlids so pretty hardy. I've also got a batch of discus separately quarantined (coming 3 weeks) and about to complete prophylactic deworming in a few days. Once the discus have completed their deworming, can I introduce the dwarf cichlids into the discus quarantine tank for a week to confirm that there's no cross contamination before putting the dwarf cichlids into the main display tank?

The best way would be to add one of your discus to the Dwarf cichlid tank so if a problem its not all your discus. Most likely you will have no issues as the main concern with across species pathogens is mostly protozoans (ex..oodinium) and some really pathogenic bacteria. These would have shown in the lengthy QT you did on the Dwarfs. And since dewormed thats not an issue.

al

[illumnae]

Great thank you!

If my 2 batches of discus come from the same breeder, and are sent directly from the breeder's farm to my house, it's safe to assume that fish tested to be safe with my 1st batch of discus would most likely also be safe with my 2nd batch of discus right? Assuming all fish go through the 6 week quarantine and deworm process

[brewmaster15]

Great thank you!

If my 2 batches of discus come from the same breeder, and are sent directly from the breeder's farm to my house, it's safe to assume that fish tested to be safe with my 1st batch of discus would most likely also be safe with my 2nd batch of discus right? Assuming all fish go through the 6 week quarantine and deworm process

Technically yes however when you say "breeder" its a term thats misused. Often times " Breeders" aren't breeding everything or sometimes anything at all. Many "Breeders" are actually just resellers. They buy from multiple sources and resell. This isnt bad in of itself and allows a seller the abiliy to offer many strains at various sizes. However it inherently comes with the risk that somewhere along the supply line pathogens are introduced.


Al