Fallow periods: Going Fishless

[Humblefish]

In fallow can I add inverts and corals?

Yes, but it restarts the fallow period every time you add a new coral or invert.

 

[kpdiver]

History...

I had a velvet outbreak in my 300 gal system in late May. I lost many fish but was able to save a few. The DT has been fallow since May 22. Just inverts and anemones remain in the DT. The survivors are currently in QT with copper power at 2.5 ppm. I have been transferring them every 3 days to another tank at 2.5 ppm copper power. The previous tank is then completely cleaned and wiped down before allowing it to air dry for 2 days before refilling and dosing copper. They will be in copper at 2.5 ppm for a total of 14 days. Prior to the copper treatment they were in CP for 7 days. I had to remove them and put them into an untreated sterile tank because I was losing fish in the CP.

My questions...

Can I add Prime to the treatment tank to help with ammonia spikes between transfers?

I'm not planning to add the fish back to the display until after August 20th. That would be 90 days fallow without raising the temp of the DT. Will this be long enough to kill all parasites and diseases?

 

[Humblefish]

Can I add Prime to the treatment tank to help with ammonia spikes between transfers?

Yes. Prime is safe to use with Copper Power. But NOT Cupramine.

I'm not planning to add the fish back to the display until after August 20th. That would be 90 days fallow without raising the temp of the DT. Will this be long enough to kill all parasites and diseases?

Yes

 

[kpdiver]

Yes. Prime is safe to use with Copper Power. But NOT Cupramine.


Yes

Thank you sir.

 

[Cor4eyh]

Just finished my fallow period after losing a few fish from velvet. I went to the lfs last night and got some black mollies hoping to check before I put my quarantined and last surviving fish from the DT.
Bought 3 lyre tail mollies as the black mollies had ich and were sick already.
Within a few hours all 3 mollies were stuck agains the overflow. Dead. Don’t think they acclimated well. They didn’t appear to have anything on their bodies as of yet. But I’m guessing just try again with some more mollies or trust that my fallow was successful?

I drop acclimated them over 3 hours with a heater in the tank to keep the same temp.

I’ve read the black mollies, sailfin mollies, and balloon mollies are the best to transition to salt water.

is there any other way to transition mollies to salt?

or other ways to test for velvet and ick?

 

[Humblefish]

I drop acclimated them over 3 hours with a heater in the tank to keep the same temp.

I’ve read the black mollies, sailfin mollies, and balloon mollies are the best to transition to salt water.

is there any other way to transition mollies to salt?

or other ways to test for velvet and ick?

You can send off for an @AquaBiomics test to screen for pathogens in your DT: Introducing the tankDNA Test

When acclimating mollies from full freshwater to full saltwater (35ppt), you will need to spend several days drip acclimating them in a bucket or small aquarium.

 

[Bshonesy]

You can send off for an @AquaBiomics test to screen for pathogens in your DT: Introducing the tankDNA Test

When acclimating mollies from full freshwater to full saltwater (35ppt), you will need to spend several days drip acclimating them in a bucket or small aquarium.

Only be aware this test can take 6 weeks to come back depending on when you send it. I think it’s a great service though and if more start using it maybe they can run batches more frequently.

 

[AquaBiomics]

Only be aware this test can take 6 weeks to come back depending on when you send it. I think it’s a great service though and if more start using it maybe they can run batches more frequently.

Thanks @Bshonesy


The turnaround time for these samples depends on when your sample arrives at our facility. If it arrives late in a batch, it should be completed within about 3 weeks. If it arrives early in the batch, it will take about 4 weeks. Sending in your sample right before the deadline will cause the least amount of delay. How long does it take to get my results?


You can check the status of the samples at any time at the following link.
Sample Testing Queue

Yes, we'd love to have more samples but, unfortunately there is only 1 Eli

~Melissa

 

[brandon429]

Why is it accepted that the very small test areas sent for DNA sampling reflects accurately that the entire system is free of a pathogen? Testing .001% of the surface or that much water out of 250 gallons is really a fair representation for the other portions of the tank untested?

 

[Amy M]

Will a fallow period work to get rid of lymphocytis in your system?

 

[Njh48310]

Going Fallow
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The reason to go fallow (fishless) is to eliminate a fish disease from your DT (display tank). Going fallow works because you are denying the disease a fish host to feed upon, essentially starving it to death.

In order to go fallow you must remove ALL fish from your DT. If just one fish is left behind, even a “disease resistant” species, then going fallow is for naught because the disease will continue its life cycle. Corals/inverts can be left in the DT, as those are not capable of hosting - although some are capable of “housing” the encysted stage of certain parasites for a period of time (see “Fallow Periods” below). It is important to continue to feed your corals/inverts while going fallow, and also put a pinch of flake or pellet food into the DT every 2-3 days to feed nitrifying bacteria in the absence of fish poop. Some hobbyists even resort to dosing phosphate & nitrate if those parameters fall too low. Continue to do everything normally with your tank whilst going fallow; although you may wish to go lights out if you are running a fish only system (just don’t forget to feed that bacteria!)

Fallow Periods - Below is the general consensus fallow periods for all diseases that require it. In most cases, it is the longest known time period that the encysted stage can survive on corals, inverts, rocks, substrate without a fish host to feed on. The fallow period starts when the last fish is removed from the tank.

• Black ich (turbellarian worms) - 4 weeks
• Brooklynella aka “Clownfish disease” or “Brook” - 6 weeks
• Flukes (monogenean worms) - 4 weeks
• Ich (Cryptocaryon irritans) - 6 weeks IF 27C/80.6F can be continuously maintained
• Uronema marinum - No fallow period, as it does not require a fish host to survive. It is an opportunistic parasite that strikes when a fish’s immune system has been compromised. Uronema mainly affects damsels (especially chromis) and clownfish.
• Velvet (Amyloodinium) - 6 weeks

During the fallow period, the fish must be quarantined and treated for whatever disease(s) are afflicting them (see links below). Successful treatment is imperative to avoid disease(s) from being reintroduced into the DT:

Fish Diseases

Medications and Treatments

Quarantining all future livestock purchases is also very important to avoid having to go fallow again in the future: How to Quarantine

After the fallow period has ended, it is a good idea to test your DT with 2-3 freshwater black mollies to ensure no diseases are still present. A freshwater black molly will have no immunity to marine diseases, and evidence of ectoparasites (white spots) or flukes (translucent spots) are easier to see on a dark coloured fish. More information here: Black Molly Quarantine

Once you are ready to start returning your fish to the DT; I recommend doing it a few fish at a time, spread out over a couple of weeks. This will give your bacterial levels time to adjust to the added fish bio-load, and avoid a potential mini-cycle/ammonia spike. I also prefer to add back smaller fish first, so they are established ahead of the larger, more aggressive ones.

Do be sure to closely monitor your ammonia levels while adding fish back. I advocate using a Seachem Ammonia Alert badge for constant monitoring:

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I had what I believe was an inch outbreak on my DT. I lost all of the fish. It’s been fallow ever since and I currently am wrapping up my 30 day copper treatment with new fish. My question is I was basing my fallow period on the 77 day rule. Looking at what’s posted here looks like I am going overboard. My tank has been and is always kept at 80.5 degrees. My tank has been fallow for 56 days as of today. Am I safe to proceed adding fish once my quarantine is completed?

 

[Ks4726]

They revised the 77 day theory based on ich life cycle at certain temp. But it needs to be 80.6. Does your .1 degree difference make a real difference? I don't know. I doubt any thermometer is exactly precise.

In theory over 6 weeks you should be good. Do failures after going fallow happen? Yes but you never know the exact cause why. You could try the molly method or aquabiomics test to see for sure. Aquabiomics would put you out another 30+ days for the results though. Defeats the purpose of the question.

 

[TheWyldZone]

In some cases, Brook can live free floating in the water (or in the rocks) for up to 6 weeks. Without feeding on a fish host.

Its Ich theronts that have to find a fish host within 48 hours or die. Velvet free swimmers can actually survive for up to 15 days because they are capable of using light as photosynthesis for energy.

It's an interesting topic in it's own right. How long marine organisms can go without direct feedings.

Inverts DOMINATE. To the extreme. Most Atlantic intertidal crabs can go 5 months. Some hermits 7 months. Some crabs 8 months. Most sea hares 3 weeks. Most Elysia 7 months+. Onchidella floridana 12 months+. Longspine urchins, 3 weeks. Rock boring urchin 8 months. Green Stripe hermits 8-16 months.
False Limpets 4 weeks
Fuzzy Chiton in the wild 1 year.

There's more but I digress.