When you assume your tank has ich...

[Clarinuto]

I’ve been reading about people’s varying opinions regarding whether a tank always has ich or not. If the assumption is that your tank always has ich or some other type of disease potentially looming, what does a person do when introducing new fish to the tank who will undoubtedly be stressed and therefore have lower immunity? Even if these fish are quarantined, being caught and transferred is stressful. Does that mean that the tank is always carrying the potential for disaster every time a change, especially to livestock, is made?

 

[EmdeReef]

I’ve been reading about people’s varying opinions regarding whether a tank always has ich or not. If the assumption is that your tank always has ich or some other type of disease potentially looming, what does a person do when introducing new fish to the tank who will undoubtedly be stressed and therefore have lower immunity? Even if these fish are quarantined, being caught and transferred is stressful. Does that mean that the tank is always carrying the potential for disaster every time a change, especially to livestock, is made?

Not all tanks have ich. that’s a common misconception but untrue. Cryptocaryon irritans is an obligate specialist, meaning it requires a fish host to feed on in order to continue its cycle/survive. Fish may develop varying degrees of immunity to ich and that’s probably where the misconception comes from. In other words you may have asymptomatic carriers in your tank and by adding a new fish it may get infected. If you’re lucky, your other fish that have that partial immunity won’t get reinfected during such an outbreak, but it can happen.

If you’ve never had ich in your tank the odds are high that your tank is ich free. If you did have ich then the only way to be sure is to treat all fish in copper or CP and run the tank fallow for ~75 days.

 

[CC13]

I’ve been reading about people’s varying opinions regarding whether a tank always has ich or not. If the assumption is that your tank always has ich or some other type of disease potentially looming, what does a person do when introducing new fish to the tank who will undoubtedly be stressed and therefore have lower immunity? Even if these fish are quarantined, being caught and transferred is stressful. Does that mean that the tank is always carrying the potential for disaster every time a change, especially to livestock, is made?

When I start a tank, I 100% do not have any diseases. I know this because I give my LR a bath in Muriatic acid and bleach. Both to kill any unwanted pests, and to get rid of any P04 that may have leached into the rock from the prior tank. I know at least at this stage I have zero pests, zero good or bad bacteria. I am starting from scratch.

From here you have to seed the tank. You can buy bacteria like Dr. Tim's, which I have used, but you also want to seed your LR with a couple pounds from various other tanks to get some diversity in your tank. IF you do this, you can setup a holding tank (separate from your main system), and keep the rock in there with a powerhead and heater for 72 days. This 99.9% ensures that anything on there (disease wise) will die.

From here, you buy fish and a CUC. Now for fish, I 100% QT and treat all fish like they have at least ICH and Brook, since almost all of them from the store do or at least were exposed to it while in the holding tanks. Again, 72 days, and you are pretty confident that you have removed all the diseases once they are added to your tank.

From here, I would say that you have a pretty likely chance that your tank is disease free. But where it gets risky is when you start to add snails, crabs, chaeto, macro algae or corals. Do you QT? Do you hold them in another tank, inspect and then add? Personally, I do not QT my CUC, chaeto or macro algae. I honestly just don't have the time. Technically, if you want to me 100% safe, you QT ALL wet items that are being added to your tank and ensure NO water from the store gets into your main system. Again, do you QT your chaeto? I don't.

There is no 100% proof of anything really. People have gotten ICH simply from cross contaminating their net with store water. It can be that easy. I QT all fish and corals because they have the highest chances of carrying diseases. From there, I weight the risk and odds from when I add my other stuff. You have to be realistic in your expectations for if its viable for treating EVERYTHING wet. For me, its not, but again, there is some risk that when adding stuff that haven't been in QT, unwanted diseases can come as well.

 

[Clarinuto]

Interesting point about CUC, live rock, and adding anything else that is wet. I have been thinking about that also. I definitely didn’t qt my live rock, CUC, or chaeto. I’ve also seeded the tank with phytoplankton and copepods, which seems like a safer thing to add but I have no idea whether there is potential there for disease.

I do plan on QTing fish though, but it does seem like there is no perfect answer... unfortunately!

 

[mcarroll]

It's good to question most of these things.

Ich is only one potential pathogen.

Specific immunity is only one function of the immune system.

Typical guidance tends to be hyper focused on one or two parasites and on specific immunity.

More focus needs to be placed on lowering stress and increasing fish health as this strenghthens the whole fish, which includes the whole immune system.

One complicating factor to all of that is that the way most quarantine systems are run is highly stressful.

(Google for aquaculture guides on stress or immunity. Or check out the fish section of my blog.)

 

[CC13]

Interesting point about CUC, live rock, and adding anything else that is wet. I have been thinking about that also. I definitely didn’t qt my live rock, CUC, or chaeto. I’ve also seeded the tank with phytoplankton and copepods, which seems like a safer thing to add but I have no idea whether there is potential there for disease.

I do plan on QTing fish though, but it does seem like there is no perfect answer... unfortunately!

You need to weight the risks against the rewards. If I were Jason Fox with hundreds of thousands of dollars in my tanks and my livelihood depended on selling corals, then I would absolutely 100% never risk anything and would QT EVERYTHING. Heck, I would never ever even reuse nets that had even touched saltwater other than from my own tanks and QT all corals for 6-months - the risk would be far too high.

But being realistic, placing everything wet into QT is just not realistic for me. You really can't treat macro algea (to the best of my knowledge) or CUC with copper or hypo anyways, you need to just let them run the 72 days in QT. But then what if the chaeto had pods? Can ICH survive on the pods? You see where I am going with this... there needs to be a line you draw.

I QT all fish and corals, an everything else I make sure to do my best never to add water from the store into my system. This is a hobby for me, not my livelihood.