Do I disinfect observation tank after each fish?

[Miami Reef]

After my quarantine procedure when I watch fish with black freshwater mollie for 2-4 weeks and they are free from parasites…Do I restart the observation tank?
Obviously I’m going to try my hardest to prevent any parasites: do you close observation tank after each batch of fish or do you let it run full time?

 

[Jay Hemdal]

After my quarantine procedure when I watch fish with black freshwater mollie for 2-4 weeks and they are free from parasites…Do I restart the observation tank?
Obviously I’m going to try my hardest to prevent any parasites: do you close observation tank after each batch of fish or do you let it run full time?

I keep all of my quarantine tanks running full time, so they are always ready to go, should I need to isolate a fish, or find something for sale that I really want to buy (grin). The ONLY time I restart a QT is if the fish in it died from an unresolved or undiagnosed infection - in that case, I sterilize and restart.

Jay

 

[Miami Reef]

I keep all of my quarantine tanks running full time, so they are always ready to go, should I need to isolate a fish, or find something for sale that I really want to buy (grin). The ONLY time I restart a QT is if the fish in it died from an unresolved or undiagnosed infection - in that case, I sterilize and restart.

Jay

What about if you find that a fish has ich/velvet in the observation tank? Would you restart it?

 

[Miami Reef]

I’m doing the hybrid TTM and my expectation is that I won’t have any parasites. Im doing the hybrid TTM and once completed I will observe them in a separate observation tank.

 

[Jay Hemdal]

What about if you find that a fish has ich/velvet in the observation tank? Would you restart it?

Yes - if you aren't treating with any chemotherapeutics

Jay

 

[Jay Hemdal]

I’m doing the hybrid TTM and my expectation is that I won’t have any parasites. Im doing the hybrid TTM and once completed I will observe them in a separate observation tank.

I've given you my opinion of hybrid TTM, haven't I? (grin). I'm not convinced that it controls Amyloodinium very well and I know it doesn't control Neobenedenia flukes. At any point, do you give the fish a FW diagnostic dip to screen for Neo?

Jay

 

[Miami Reef]

I've given you my opinion of hybrid TTM, haven't I? (grin). I'm not convinced that it controls Amyloodinium very well and I know it doesn't control Neobenedenia flukes. At any point, do you give the fish a FW diagnostic dip to screen for Neo?

Jay

I’ve never heard of Neo, but I’ve been talking with Humblefish about this treatment. Hybrid TTM involves 2 30 min peroxide baths spaced 6 days apart and I will treat with praziquantel too.

I will forward your message (anonymously) and see what he has to say about it.

I did not start quarantine, nor do I have any fish at the moment. My plan was to have a black freshwater mollie in observation tank for 2 weeks to ensure everything was successful.

What is neo, what does it cause for fish symptom wise, and what signs should I look out for?

 

[Jay Hemdal]

Here is an excerpt from my upcoming disease book regarding Neobenedenia. Please understand that I'm not saying your fish have this issue, just that TTM does not handle this disease effectively.


Neobenedenia melleni (eye flukes)
These are relatively large (up to 8 mm), egg-laying worms that live on the skin or eyes of marine fishes.

Symptoms
Neobenedenia infections peak slowly; there may be no symptoms for weeks after you acquire a fish. Eventually, as the flukes multiply and grow in size, they begin to cause symptoms of disease.

The first obvious symptom may be slightly cloudy eyes, caused by the transparent fluke feeding on the eye tissue and eliciting a tissue reaction. This gives this worm the common name of “eye fluke,” although it is unknown whether these worms actually prefer to feed on eye tissue, or whether that is just where they first become apparent.

As the infection becomes more serious, the fish will “flash,” their skin color will become dull, their fins may become tattered, and they just generally get a “scruffy” look to them. Rapid breathing due to stress, possible secondary infection, and then death follow if treatment is not begun.

Diagnosis
The best means of diagnosis is to give the fish a five-minute freshwater dip. Not only does this knock back the infection by killing the adult parasites, but even a casual look at the bottom of the dip container afterwards will help to positively identify this disease. The worms turn whitish and fall to the bottom. Many aquarists mistake these for scales that were dislodged from the fish. However, looking at these “scales” under a dissecting microscope, or even a hand lens, will soon show them for what they are—dead worms.

Sometimes a fish’s history can help diagnosis at least the potential for this disease. Angelfishes and butterflyfishes are especially prone to Neobenedenia infections, so any of these fish that have been housed at an import facility that doesn’t prophylactically treat for trematodes stand a very good chance of being infected.

Angelfish, Pomacanthus sp. ++
Barrimundi, Lates sp. ++
Batfish, Platax sp. +++
Butterflyfish, Chaetodon sp. ++
Cichlid, Tilapia sp. +++ (when housed in seawater)
Invertebrates 0 (but may carry eggs)
Jacks, Caraganidae +++
Lionfish, Pterois sp. +
Lookdowns, Selene sp. +++
Pyramid butterflyfish, Hemitaurichthys sp. +++
Grouper family, Serranidae ++
Garden eel, Taenioconger sp. +
Remora, Echeneis sp. +
Sharks and rays, Elasmobranchs 0
Surgeonfish, Acanthurus sp. ++
Spadefish, Chaetodipterus faber +++

Aquarium hosts for Neobenedenia sp. 0=not infected, + = sometimes infected, ++=commonly infected, +++=very commonly infected (From Bullard et-al 2000 and personal obs.)

Treatment
Many people suggest using a freshwater dip as a treatment for all incoming fish. The two drawbacks to this are 1) the dips are not 100% effective (and do not harm the fluke eggs) and 2) newly acquired fish often do not stand up well to the added stress of a freshwater dip when they first arrive.

Neobenedenia eggs can take 14 to 30 days (or longer?) to hatch as motile larvae called oncomiracidium. Additionally, the eggs have sticky tendrils that attach them securely to all manner of objects in an aquarium. There is some merit to the idea of keeping a treatment tank free of substrate and siphoning the bottom regularly in order to remove some of these unhatched eggs. There have been reports that Lysmata cleaner shrimp feed on these eggs, rendering them non-viable. However, it is unlikely that in a normal aquarium, with many other food choices, that cleaner shrimp will markedly reduce their numbers.
Any successful treatment for these worms must be undertaken in stages. The first treatment kills off the adult worms (but this won’t kill the eggs), and the subsequent treatments kill off the juvenile worms after they have all hatched but before any of them have matured and begun to lay eggs of their own. Due to variables in timing, it is virtually impossible to accomplish this in only two treatments.

Whole-tank formalin baths at 166 ppm for one hour will eliminate the adult flukes from an aquarium but not the eggs. Because this type of treatment has no residual effect, the treatment may need to be repeated every two weeks for two or three more times. Experience in public aquarium exhibits has shown that this method rarely clears a tank completely of this pest.

A better alternative is a Praziquantel treatment at 4 ppm, followed by a 50% water change after 48 hours, then a second treatment 12 to 14 days later, followed by another 50% water change 48 hours later.

At the Toledo Zoo Aquarium, we noticed that multiple Praziquantel treatments on the same system, over months to years, required higher and higher doses, combined with increased frequency of the treatments in order to maintain effectiveness. Eventually, the praziquantel was simply no longer effective. One supposition was that the target parasites were building an immunity to the drug. That seemed unlikely as genetic change in multi-cellular organisms typically takes longer to happen (as opposed to drug-resistant bacteria that can develop resistance in short order). We wondered then, what could be rendering Praziquantel so ineffective on repeat doses?
Subsequent research indicates that bacterial degradation of the Praziquantel (Thomas et-al, 2016) is the process at work. Their study concluded that while Praziquantel is stable for over two weeks in sterile marine aquarium water, when dosed in working systems, it degrades below detectable limits in just nine days. A subsequent dose on the same system showed a reduction in Praziquantel in less than 48 hours. The presence or absence of fish in the system did not affect this rate of degradation. The natural bacterial population of the aquarium actually works to eliminate Praziquantel from the water.

Barrett L. Christie, a public aquarium curator, has researched a variety of treatment methods and has struck upon one that is highly effective. The treatment is relatively simple; in a quarantine system, the fish are exposed to hyposalinity (low salinity) for 35 days. Exactly how low of a salinity is the variable that needs to be controlled. Some species of fish do not tolerate lower salinities, yet if the salinity is not reduced enough, the parasite population is only reduced, not eradicated. Barrett has hit upon a workable value of 17 parts per thousand, a bit less than half the salinity of normal seawater (this equates to a specific gravity of around 1.013). Obviously, most invertebrates cannot be present during this sort of treatment. Sharks and some rays cannot tolerate it either. Assuming the fish are healthy in all other respects, you begin this treatment by lowering the salinity to the target value over 24 to 48 hours. During the low salinity treatment, water quality must be monitored closely, especially pH. Be aware that some other diseases, notably Uronema and Amyloodinium thrive at lower salinities. Luckily, another common scourge, marine ich, Cryptocaryon irritans, is also inhibited by low salinity. After 35 days, the salinity is gradually raised back to normal. It is imperative to perform this change back to normal seawater very slowly. While marine fish tolerate a drop in salinity very well, their kidneys have more difficulty adjusting as the salinity is raised. Never return fish to normal salinity faster than 72 hours, and don’t make large changes at one time.