High Tide Aquatics

Article series: the how, why, and whether-I-should of quarantine

IOnceWasLegend

Frag Swap Coordinator
BOD
Starting this off with a disclaimer: I think quarantine (QT), like many things in reefkeeping, is a matter of personal tolerance for risk and balancing your enjoyment of the hobby. This guide is not meant to be judgmental, or to argue people cannot have success in their tanks without QT. It’s meant to provide a guide for someone who’s considering QT to learn the why, the what, and the general ‘how’ of QT.

Part One: To QT or not to QT?

I would wager my story is a familiar one in reefing: I started with a small tank before upgrading. My new tank was bigger, so I added more fish. Everything was going well, until one day it wasn’t, and a disease outbreak (velvet) wiped out the tank. While it’s important to note this doesn’t happen to everybody, it can happen to anyone—just like it happened to me.

This sparked my interest in fish health, disease treatment, and the eventual decision to do a fully-quarantined display tank. However, it took a lot of digging and research to get a better idea of what to do, so I decided to make this guide.

The purpose of this guide is not to discuss the nitty gritty details of setting up a QT system. Instead, it’s meant to provide a higher-level view of why you may (or may not) want to consider a QT system, the various approaches and alternatives you can take to setting one up, and—in general—to give you the resources you need to answer the question, “Is it worth it to me?”

So why should I consider a QT’d system?

Maybe you heard QT can be healthier. Maybe you're like me and had disease wipe out a tank. Maybe you take BAR’s mission statement super seriously. Whatever your reason, the general ‘why’ of considering a QT system usually falls under:

Diseases suck, both for the animals in our care and the hobbyist caring for them, and quarantine helps prevent them

These diseases can range from uncomfortable (skin and gill flukes that cause scratching and flashing behavior in fish), to outright deadly (marine velvet causing fish to rapidly suffocate). They can also take away from your enjoyment of the hobby, when treatment protocols can be merely annoying (medicating your fish’s food) to maddening (having to pull every fish from your tank, put them in a separate tank, treat with a cocktail of medications, and keep them alive for 76 days until the disease starves in your tank).

While most things get easier in a larger system, dealing with diseases is not one of them. The larger your tank, the larger the risk becomes. Each new addition represents not only a potential vector, but also increases the ‘cost’ of failure if there’s a disease outbreak that you decide to treat (more QT tanks required, more expense to replace fish, etc.)

Additionally, some fish that are common in larger systems—particularly tangs, and especially acanthurus tangs (achilles, powder blue, powder brown, etc)—are highly prone to marine ich and marine velvet, two of the most difficult diseases to treat (and, in the case of velvet, one of the deadliest). Other fish, such as the common blue-green chromis, are frequent carriers of uronema.

It’s important to note that no quarantine protocol is 100% effective. However, when done properly, it does help prevent the overwhelming majority of these diseases and can result in healthier fish overall.

Price considerations

While I believe the health of the animals under our care is the most important reason to quarantine, I’m going to focus purely on the financial aspect to start. This is because, in my experience, people tend to be extremely price-sensitive when it comes to quarantine.

Setting up and running a QT system is more costly, both in terms of money and energy, than a normal system. Similarly, purchasing pre-QT’d fish will be more expensive than purchasing “conditioned” or non-quarantined fish. More sensitive and/or more difficult to QT fish (copperband butterflies, moorish idols, etc) will be proportionally more expensive.

While the upfront costs are higher, I encourage you to weigh them against the costs of replacing livestock lost due to disease (to say nothing of the emotional aspect of losing animals you care about). Weigh not just the price difference of a quarantined fish, but how much it would cost to replace that fish, and how willing you are to take that risk.

With that being said, the specific requirements will vary depending on the type of quarantine that’s chosen. In the next sections, I’ll cover observation versus management versus quarantine, the pros and cons of each, and what they require.
 
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Part Two: Preventing disease when adding fish to your tank: Observation versus quarantine versus management

There are several, non-mutually-exclusive levels of disease prevention you can perform for fish you purchase before adding them to your tank. Each has its benefits and drawbacks, and which (or whether) of them you use will dictate how much time and/or energy you have to commit.

The first of these is observation. This involves setting up a second tank at least ten feet away from your display tank (the minimum ‘safe’ distance, since some parasites can spread from aerosol transmission from one tank to another), and observing the fish for any signs of illness over a period of time (typically ~30 days).
  • Pros:
    • Simplicity
    • Some vendors run hyposalinity and/or sub-therapeutic levels of copper to suppress disease; can give a more accurate impression of fish's actual health
    • Allows the fish to ‘recover’ in a low-stress environment after the stress of collection/transport
    • Time can be used to feed high-quality food/supplements
  • Cons:
    • Requires dedicated observation time (~30 minutes is ideal) every day
    • Some diseases may have extremely subtle symptoms, or have minimal time between ‘symptom presentation’ and ‘death’
    • If fish does present with illness, a third tank is required for treatment

A second approach is quarantine. In this method, you set up a second tank (again, at least ten feet away from your display tank) and treat the fish with copper and a variety of medications for at least two weeks. Following this, it’s advised (though not strictly necessary) to follow up with observation prior to placing the fish in your display tank. A full guide on setting up a QT tank can be found here, and a detailed guide for medications to use can be found here.
  • Pros:
    • The most effective strategy at preventing disease
    • Necessary to ensure disease eradication (or as close as is reasonably possible)
    • Allows the use of non-reef-safe medications
  • Cons:
    • Copper (and other medications) can suppress appetite
    • Some fish are extremely difficult to QT, either because of diet (e.g. mandarin dragonets) or because of medication sensitivity (e.g. chromis, anthias, etc)
    • Some medications can either be difficult to obtain (chloroquine phosphate) or are extremely toxic to people (formalin)
    • Depending on how many fish need to be QT’d, may require multiple tanks given concern of ammonia build-up with high bioload
    • Chemical quarantine can be very stressful on fish, and even moreso for fish that are already not doing well; pros of treatment must be weighed against condition of fish + severity of illness

Finally, there’s management. This approach relies on high water quality, UV sterilizers, high-quality fish diet + supplementation, possibly hydrogen peroxide dosing (see below) and more. In general, anything that minimizes disease risk and/or improves the fish’s overall health to help their natural immune system fight off disease falls under this category.
  • Pros:
    • Arguably the simplest method, since it’s an extension of the husbandry already being done
    • Good for your livestock, even without disease, since it helps keep them happy and healthy
    • Preliminary data suggests hydrogen peroxide dosing may be helpful in controlling (but not necessarily eliminating) otherwise-difficult-to-treat illnesses
  • Cons:
    • Emphasizing this given how often it’s conflated: Management is NOT eradication. This method suppresses disease (if present in your tank), but stressful events can quickly lead to a breakout in a seemingly-healthy tank
    • May be less effective for sensitive fish/fish with thin slime coats (powder blue tangs, achilles tangs, etc)

This list of pros and cons is not exhaustive, and there are other approaches (such as the tank transfer method). However, these represent a reasonable starting point.

Additionally, the approaches listed here are not mutually exclusive: for example, a ‘gold standard’ quarantine protocol may incorporate quarantine, followed by a lengthy observation period, with prophylactic management strategies for your display tank. Whatever strategy(s) you decide to follow, however, depends entirely on your personal tolerance for risk + balancing time/money investment with your enjoyment of the hobby.

For further reading, here is an excellent article that goes more in-depth into the methods, pros, and cons of observation versus quarantine. Additionally, if you want to start looking more into the ‘how’ of quarantine, I suggest (what I consider to be) the definitive guide to fish quarantine.

This section covered the various types of disease prevention when adding fish to your tank. The next section will cover how coral, snails, and macroalgae can also act as disease vectors into your tank, and steps you can take to prevent it.
 
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Part Three: Stony coral, snail shells, macroalgae, and other potential vectors of disease

Some of the ways diseases get into your tank are obvious: an infected fish, contaminated water, etc. Some, however, are less obvious: that snail (or shrimp) you just added. A piece of stony coral. Macroalgae. This doesn’t make intuitive sense—ich and velvet (the main diseases I’ll focus on in this section) are fish diseases. How can other organisms carry them?

The answer lies in the life cycle of these organisms. Stealing (and crediting) a picture from Humblefish’s excellent thread on marine ich:

ichcyclegraph.jpeg

Credit: Charles Raabe

The ich lifecycle is simple: a parasite ‘hatches’, swims until it attaches itself to a fish host, drops off, adheres to a hard substrate, reproduces, and then the next generation hatches and restarts the cycle. The lifecycle is much the same for velvet.

That ‘adherence’ step is what causes our headaches. During that stage of their lifecycle, ich and velvet tomonts can adhere to virtually any hard surface: frag plugs, coral skeletons, rubble, snail shells, shrimp exoskeletons, etc. Given their small size, strong adherence, and uneven surfaces they can adhere to, it’s also virtually impossible to reliably scrub tomonts off. So even if none of your fish are sick, adding a piece of coral from an infected tank can kick off an outbreak in yours.

So how do we prevent it?

In another excellent Humblefish thread (noticing a pattern yet?), Bobby dug up what is likely the only research article detailing encystment timeframes for marine ich. There are some exceptions, but the short version is—the safest thing to do is quarantine your coral, snails, invertebrates, etc. in a fishless system for 45 days at 80.6 degrees fahrenheit.

Without a fish to infect, ich, velvet, and other diseases can’t reproduce, so you’re just starving them out. 80.6 F is a bit on the high side, temperature-wise, but the higher temperature drastically speeds up the parasite lifecycle (versus 72 days at 78 F). It should be noted, however, that—unlike fish quarantine—adding more coral/inverts/etc to your QT system does not reset the 45-day timer on the other pieces, since tomonts cannot ‘jump’ from one hard surface to another.

That seems like a massive pain in the tailfin

It is indeed, and it is one of the biggest points of consideration when debating whether (and the extent to which) you’ll quarantine. Complete biosecurity requires you to effectively quarantine everything wet that goes into your tank: fish, invertebrates, corals, and macroalgae. However, it is also inconvenient, frustrating (in the event of losses), and delays gratification. Furthermore, it’s hard to say exactly what the likelihood/risk of infection is, so—again—it is purely a matter of your personal tolerance for risk.

For myself—I QT everything wet that comes into my tank for 45 days at 80.6 F (more like ~81 F) in a fishless system. The exceptions are fish and inverts from quarantined vendors (see below). My rationale is that I’ve already invested this much time, expense, and effort into a fully quarantined system, and I’d rather avoid the risk, however slim. Plus it has the benefit of forcing me to be patient and plan out what I am doing long-term.

Skipping the wait: Quarantine vendors

A preface to this section: these are my individual opinions, and should not be taken as an endorsement by BAR as a whole/by the Board of Directors.

In case it was not clear at this point, I consider Humblefish to be the gold standard for fish care and health. They maintain a list of trusted quarantined livestock vendors.

One such vendor is our very own High Tide Aquatics, run by Kenny (@under_water_ninja ) in Oakland, CA. Again emphasizing this is my personal opinion: I cannot recommend Kenny enough. With the exception of four fish (two I QT’d myself, two being species Kenny does not QT), every single fish in my tank is from him. He is passionate and extremely knowledgeable about fish husbandry, truly cares for the animals in his care, is extremely transparent with his methods, and is also the only brick-and-mortar Humblefish-certified vendor in the country. You can see his interview with Humblefish, and I highly recommend he be your first stop if you’re considering purchasing QT’d fish.

Another local option for quarantined coral is KaysCoralCove, run by @Arvin R in Castro Valley. While they are not (yet) a certified Humblefish vendor, their QT protocols are in line with what Humblefish recommends. They carry a wide range of different corals, ranging from hobby staples to extremely nice SPS and torch corals. To date, they’re the only vendor I’ve found that offers high-end QT’d corals.

While not a local option, Inverted Reef is a fantastic, Humblefish-certified option for quarantined invertebrates and macroalgae. They’re fairly new, but Tim and Heather have been nothing short of an absolute pleasure to work with. They were more than happy to work with me and coordinate custom orders to help build my CUC for my display tank.

A word of caution about Dr. Reef

Dr. Reef is a vendor that offers conditioned and quarantined fish. While they were once a Humblefish-certified vendor, that is no longer the case; this thread does a reasonable job explaining why.

I have not had any direct dealings with them. Anecdotally—I have seen a rather large number of complaints regarding unhealthy and/or obviously infected fish, diseases introduced to tanks shortly after adding fish, and poor communication. I also know people (members of this community, in fact) who have had positive experiences and would recommend him.

Take everything I (and others) say with a grain of salt. Personally, given his removal as a Humblefish-certified vendor and the persistent issues, I would not recommend using him, particularly when we have other options in our own backyard.
 
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The worst feeling is just as you are about to complete your fish collection, that last fish comes with something and starts wiping out your tank 1 by 1.
100%. I'm reasonably certain that my tank wipe (fish seemed healthy, then I had to transfer tanks due to a near seam blowout, then velvet cropped up a day later and wiped everything out) was due to the last fish I added.

That sick feeling of watching my fish die one by one has never left me. I know a common sentiment is "they're just fish", but—we control literally everything about their existence and their lives. They died because I did not take proper precautions, and because I was not equipped to save them when they started showing symptoms. I have zero interest in ever letting that happen again.
 
100%. I'm reasonably certain that my tank wipe (fish seemed healthy, then I had to transfer tanks due to a near seam blowout, then velvet cropped up a day later and wiped everything out) was due to the last fish I added.

That sick feeling of watching my fish die one by one has never left me. I know a common sentiment is "they're just fish", but—we control literally everything about their existence and their lives. They died because I did not take proper precautions, and because I was not equipped to save them when they started showing symptoms. I have zero interest in ever letting that happen again.

Velvet is brutal. I never used to QT and treat fish, but velvet is what made me start doing it. 80% mortality in less than five days.
 
Velvet is brutal. I never used to QT and treat fish, but velvet is what made me start doing it. 80% mortality in less than five days.
Velvet still gives me nightmares. It killed every fish in my RSR250 in less than 48 hours, except for a watchman goby and an algae blenny (which, ironically, I still have both of them).
 
Just my 2 cents, this series would make a great follow along type of weekly content post for the Facebook/Instagram pages. It definitely speaks to me about what bar is about. It would show some of what we have to offer. I could also see this type of thing expanding to other subjects as well within reefing.

Also I love the way your writing this, very informative yet not so indepth that it sounds like your speaking an alien language, provides detailed information, links to and cites sources, not attempting to sway anyone one way or the other, it’s not argumentative, and it pulls you in.
 
Just my 2 cents, this series would make a great follow along type of weekly content post for the Facebook/Instagram pages. It definitely speaks to me about what bar is about. It would show some of what we have to offer. I could also see this type of thing expanding to other subjects as well within reefing.
Thanks for the idea! If we wanted to do this, I'd be happy to write up social media posts (@ReyDeFarts would that be you posting them)?

Also I love the way your writing this, very informative yet not so indepth that it sounds like your speaking an alien language, provides detailed information, links to and cites sources, not attempting to sway anyone one way or the other, it’s not argumentative, and it pulls you in.
And very much appreciated on this. My 'day job' is as a scientific writer, and I got into it because there's a stunning lack of overlap between 'knowledgeable people', 'people who can communicate that expertise clearly', and 'people who can (mostly) put their bias aside'. On that note, I think people who've been in the hobby for any length of time tend to forget just how hard it is starting from scratch, and how much knowledge we take for granted.

I think the most useful thing I ever learned was a quote from Carl Sagan. Paraphrasing, he said that he had never been the smartest person in the room, and he had to work to understand things. But that meant that he remembered where he stumbled, where he fell, where he had trouble learning something, and how he learned it; and that let him 'over-engineer' those sections when he explained it to other people.
 
Part 1 posted on Facebook, Part 2 will be released today. I simply copied and pasted (if you would like credit, can tag you as well)

Instagram will be getting an update as well, Just need to find the right photo to part with.
Sure; if you don't mind putting my name (Josh Azevedo) on there, I'd appreciate it. :) Otherwise, thank you, and hope this gets some use!
 
Thanks for taking the time to write this up, lots of good general info. I also learned a hard lesson early on and have since bought all my fish from Kenny. The cost is 100% worth it. To be honest, I'd probably be willing to pay even more. Especially for fish with longer life spans - I don't understand the reluctance to pay a little more $$ for something that may live 15+ years.

One thing I feel like is an omission from the "Cons" of quarantining, though, is the stress that it induces. Fish seem so incredibly prone to stress, in my experience. QTing is a stressful experience. I often see people pulling all their fish and subjecting them to tons of treatment at the first sign of an illness, and wonder sometimes if we do more harm than good.

I find stress is often what triggers disease outbreaks. I 100% of have ich in my tank. It very rarely makes an appearance, but when it does it's always because of some stressful event. I don't yank all my fish and freak out and start going fallow - I just feed more, a lot more.

Last note about Dr. Reef - I had a terrible experience with them. Lots of dead fish. Yes, they provide store credit. But I had a hard time actually spending it because fish simply would not survive from that vendor. I have avoided them ever since discovering High Tide.
 
Thanks for taking the time to write this up, lots of good general info. I also learned a hard lesson early on and have since bought all my fish from Kenny. The cost is 100% worth it. To be honest, I'd probably be willing to pay even more. Especially for fish with longer life spans - I don't understand the reluctance to pay a little more $$ for something that may live 15+ years.

One thing I feel like is an omission from the "Cons" of quarantining, though, is the stress that it induces. Fish seem so incredibly prone to stress, in my experience. QTing is a stressful experience. I often see people pulling all their fish and subjecting them to tons of treatment at the first sign of an illness, and wonder sometimes if we do more harm than good.

I find stress is often what triggers disease outbreaks. I 100% of have ich in my tank. It very rarely makes an appearance, but when it does it's always because of some stressful event. I don't yank all my fish and freak out and start going fallow - I just feed more, a lot more.

Last note about Dr. Reef - I had a terrible experience with them. Lots of dead fish. Yes, they provide store credit. But I had a hard time actually spending it because fish simply would not survive from that vendor. I have avoided them ever since discovering High Tide.
Very good point; I noted that some fish were difficult to QT, and there's a discussion in the 'observation vs QT' thread I linked, but I didn't outright state this. Fixed this by adding a bullet to the 'cons' section:

  • Chemical quarantine can be very stressful on fish, and even moreso for fish that are already not doing well; pros of treatment must be weighed against condition of fish + severity of illness
 
Thanks for taking the time to write this up, lots of good general info. I also learned a hard lesson early on and have since bought all my fish from Kenny. The cost is 100% worth it. To be honest, I'd probably be willing to pay even more. Especially for fish with longer life spans - I don't understand the reluctance to pay a little more $$ for something that may live 15+ years.
This is specifically why I built that section on 'price' in as part of the first paragraph. The price sensitivity is ridiculous, given it makes both financial (long-term) and animal-health sense. Copy-pasting a response I wrote about Kenny's shop on HF last year:

I think it ultimately boils down to "people are bad at understanding the full costs of something, and get upset when it impacts them/doesn't match what they expect to pay."

Noting that this is all purely conjecture on my part, as I am not affiliated with Kenny's business in any way, but I'd imagine it goes something like this:

What the average customer sees:
  • The cost difference between a fish at Kenny's versus one at another store
What the average customer does not see (all separate from the 'normal' costs of an LFS):
  • The costs incurred by trying to source the healthiest, rather than the cheapest, fish
  • The costs associated with optimizing the methods to achieve high QT success rate
  • The costs of the medication used to treat the fish throughout quarantine
  • The costs of the electricity, salt, water, etc. to run the QT side of things prior to the fish being put up for sale
  • The cost of labor for the person doing not only the QT, but also planning/juggling multiple fish going into and coming out of QT
  • The costs of livestock that does not make it through (which includes the initial cost of the fish and everything else I listed above)
  • Plus, I'm sure, a bunch of other stuff I'm not considering
Add this to the fact that none of this is an immediately apparent benefit to the customer ("That wrasse looks healthy at the other shop"), and that people typically don't like paying for non-flashy prevention/safeguards (see: why IT is usually underfunded in most companies), and I think that about sums it up.

TL;DR: Paying $150 for a healthy fish, when you could have a (potentially infectious) fish AND coral for the same price, feels bad and the average customer doesn't consider that the two fish aren't really comparable.
 
This is specifically why I built that section on 'price' in as part of the first paragraph. The price sensitivity is ridiculous, given it makes both financial (long-term) and animal-health sense. Copy-pasting a response I wrote about Kenny's shop on HF last year:

I think it ultimately boils down to "people are bad at understanding the full costs of something, and get upset when it impacts them/doesn't match what they expect to pay."

Noting that this is all purely conjecture on my part, as I am not affiliated with Kenny's business in any way, but I'd imagine it goes something like this:

What the average customer sees:
  • The cost difference between a fish at Kenny's versus one at another store
What the average customer does not see (all separate from the 'normal' costs of an LFS):
  • The costs incurred by trying to source the healthiest, rather than the cheapest, fish
  • The costs associated with optimizing the methods to achieve high QT success rate
  • The costs of the medication used to treat the fish throughout quarantine
  • The costs of the electricity, salt, water, etc. to run the QT side of things prior to the fish being put up for sale
  • The cost of labor for the person doing not only the QT, but also planning/juggling multiple fish going into and coming out of QT
  • The costs of livestock that does not make it through (which includes the initial cost of the fish and everything else I listed above)
  • Plus, I'm sure, a bunch of other stuff I'm not considering
Add this to the fact that none of this is an immediately apparent benefit to the customer ("That wrasse looks healthy at the other shop"), and that people typically don't like paying for non-flashy prevention/safeguards (see: why IT is usually underfunded in most companies), and I think that about sums it up.

TL;DR: Paying $150 for a healthy fish, when you could have a (potentially infectious) fish AND coral for the same price, feels bad and the average customer doesn't consider that the two fish aren't really comparable.
Being focused on the price for a fish seems to be ridiculous for those who have invested a ton of money in their tanks.

But not everyone has and for them, it is not clear why a fish cost twice as much there vs somewhere else. Like most of this hobby, it is about knowledge and experience. The majority does not have either if I might make this provocative statement.

And others do their own quarantine - I have done it once, it was successful, but far too time consuming. Certainly not worth the effort for me.

And then there is Paul Baldassano who believes proper feeding will cure anything, and that quarantine reduces the live expectancy of the fish.
 
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