Fallow period for cryptocaryon irritans (ich)

[seahorsedreams]

That's why I was confused. I know the ins and outs of a TT and knew it would not work with corals, so I was curious what the new coral tank transfer was all about.

The transfer is performed so the Ich that was "sitting" on the bottom, doesn't reinfect the fish. When the Ich is released and there is no fish host, they will die. So yes, a QT is the proper way to go (if that's what someone is interested in).

 

[Gogandantess]

Or, you/we could relax a little like Paul B and just feed our fish live blackworms. Im going to try a little of both

I tried feeding them that and only one fish was interested in them. So that method fails.

 

[appellativo]

It took putting worms in every day for a few days before they figured it out, but now mine love them! At first they were like, 'oh crap, its moving, swim AWAY!' LOL

 

[Bunkerbean]

Why can't you treat the whole DT with copper?

 

[appellativo]

i guess you could, if you didnt have any corals, LIVE rock, or invertibrates like crabs shrimp and snails

 

[Bunkerbean]

i guess you could, if you didnt have any corals, LIVE rock, or invertibrates like crabs shrimp and snails

I have snails and a shrimp and one 10# piece of LR I care about. Zero coral

 

[blusafe]

Can I have your source for this?

"Cryptocaryon is known to infect many different fish species, although there appear to be differences in susceptibility (Wilkie and Gordin 1969; Colorni 1985; Colorni and Burgess 1997). "
http://edis.ifas.ufl.edu/fa164

Also, this studies three fishes and there were slightly different results but need more data as well.
http://www.ncbi.nlm.nih.gov/pubmed/8627500

 

[SNAKEMANVET]

This is why I do a 8 to 12 week qt on anything that has been in a saltwater tank.This is what I go by.

FAO Snorvich

Although the use of statistical analysis to illustrate the maximum tomont excystment is useful. It hasn't taken into account the published data on C.irritans tomont release. #

Peak excystment at 25C takes place at 6 +/- 2 days.

Maximum tomont excystment time was 72 days at 25C. (Colorni)

 

[appellativo]

qt is sort of worthless unless you have a treatment plan in case something shows up. Heck, you could have a constant low grade ich infection in the gills the entire time of qt, then still put it in your tank. THIS IS WHY I do Tank Transfer Method on all new fish introductions.

 

[Jackg962]

So my 93G cube does not technically start the fallow period until I get those 2 surviving Chromis out. I guess I better get busy

 

[simonh]

A normal distribution is a very important statistical data distribution pattern occurring in many natural phenomena, such as height, longevity of a member of a population e.g. human being.s For this discussion we are focused on the life cycle of Cryptocaryon irritans, otherwise known as marine ich. Certain data, when graphed as a histogram (data on the horizontal axis, amount of data on the vertical axis), creates a bell-shaped curve known as a normal curve, or normal distribution.

Do we know that the distribution for Cryptocaryon irritans follows a normal distribution? It is quite possible it may follow an alternative such as a skewed distribution with a long right tail.

If you look at the percentages of population members within a standard deviation of the mean, we see that approximately 19.1% of normally distributed data is located between the mean (the peak) and 0.5 standard deviations to the right (or left) of the mean. For Cryptocaryon irritans, we are going to assume that 68% of the members lie within one standard deviation of the mean.

If you add percentages, you will see that approximately:
• 68% of the distribution lies within one standard deviation of the mean.
• 95% of the distribution lies within two standard deviations of the mean.
• 99.7% of the distribution lies within three standard deviations of the mean.

We only need a one-sided upper limit. We are not interested in how many complete their lifecycle within the period between -2SD and +2SD (i.e. between day X and day Y). We are interested in how many have completed their lifecylce in Mean+2SD days(i.e. how many by X days). Anything less than Mean-2SD has already completed its lifecycle.

Therefore:
Mean+1SD = 84.0%
Mean+2SD = 97.7%
Mean+3SD = 99.8%

These percentages are known as the "empirical rule". What this means for Cryptocaryon irritans is that leaving a tank fallow for 3 weeks will give you a 68% chance that you have eradicated the parasite, leaving a tank fallow for 6 weeks will give you a 95% chance of eradication, but if you want 99.7% chance, you will leave the tank fallow for 9 weeks. That is the reason you see different numbers being used on Reef Central and in the literature.

It said above that the average life span was 3 weeks. Taking average to be the arithmetic mean this is 50%. I’m not sure where the 3 weeks = 68% comes. I'm not sure how these numbers were arrived at given we don't have an SD ?

I see confusion when different numbers are used for the required fallow period to make sure you tank is ich free. Perhaps this will clarify. Or not!

Isn’t it safer to just say leave the tank at least 72 days as we have published data on that number? The rest is just hypothetical dependent on the shape of the distribution and the unknown parameters. Also, unless the distribution is derived from the time it takes for a tank to be erradicated of C. irritans then it is quite hard to jump from the time to complete lifecycle to a probability of a tank been erradicated.

 

[Tevosyan]

I am now so paranoid. QT on the fish I can deal with but QT for any and all inverts, corals, live rock etc is just so much work, at least for me as I am building a 110. I too would gladly pay a premium price for a reef safe Crypto treatment.

Totally agree with You

 

[C_Aldrich]

The analysis in the initial post is severely flawed as noted above, but it is clear that the longer one waits the better. In addition to the points raised above, the cited mean value has no literature reference and there is no known standard deviation, so one can't calculate anything.

 

[VonClownfish]

I just had a bad out break, and lost some of my fish. I plan on letting the tank go fallow for the 10 week period as suggested. My fish are now in a new quarantine tank, and I am slowly raising the level of copper dose. I have a few questions. First, can I keep them in copper for the whole 10 week period and if so, at what level should I maintain it? I'm using mardel coppersafe, and my lfs said keep the copper at 2.0ppm with the A.P.I. test kit. What is the recommended safe level for prolonged treatment? Lastly, If I added more pieces of coral down the road, how do I prevent ich from hitch hiking in with the coral and or live rock its attached to?

Thanks


Sorry, can an admin move this post out of this sticky?

 

[zeebies]

Lastly, If I added more pieces of coral down the road, how do I prevent ich from hitch hiking in with the coral and or live rock its attached to?

Some think it's overkill, but I keep a QT just for rock, inverts, coral, etc. Each time I get a batch I quarantine for 10-12 weeks, then add to the display.

 

[VonClownfish]

Some think it's overkill, but I keep a QT just for rock, inverts, coral, etc. Each time I get a batch I quarantine for 10-12 weeks, then add to the display.

I'm not going through all this trouble for nothing. If that's the only safest thing to do then I intend on doing that from now on. I'm sure the corals are going to be difficult.

 

[VonClownfish]

My next question is what to do with my mandarin and scooter blenny? I've seen my mandarin eat pellets and mysis so I'm hoping he would be able to start feeding on those regularly. As for the scooter, he's very tiny, and I haven't seen him eat anything but pods in the tank. I put some live rock in the QT, I'm assuming all the pods will get killed? Any thoughts on how to feed and keep these guys alive? I'm thinking I should just give them back to the LFS since they are both pretty healthy. I'd hate for them to sit in starvation for 10 weeks.

 

[Tek]

Some think it's overkill, but I keep a QT just for rock, inverts, coral, etc. Each time I get a batch I quarantine for 10-12 weeks, then add to the display.

I followed a strict QT procedure for all fish and had a parasite free DT. Purchased 2 large snails and a week later ich visible on all of my fish!
My next CUC order will be quarantined for sure.

 

[snorvich]

For those that are "analyzing" my initial post on the subject, and pointing out what they perceive as errors, I must admit to originally simplifying in the interest of understandability. For any given salinity, temperature, light cycle, and most importantly, strain of cryptocaryon irritans, the life cycle distribution is much more likely to be Poisson rather than normal. But for the population (collection) of those distributions, as with most biological processes, the overall statistical description is likely to be normal.

However for those who are uncomfortable with the original analysis simply assume the longest reported period which is 72 days. That is probably going to be ok the vast majority of the time. For that too is a simplification as it is only for one strain of cryptocaryon irritans in one set of circumstances.

 

[Jamesg53]

I have a problem with ich in my old tank that has coral and fish. Im Just setting up a new tank that is going through cycle 8ft x 2ft x 28in with new sand and new live rock and base rock. Now what is the best way of transfering all fish and corals but making sure I don't get ich in the new tank? Should I transfer all corals first? Only fish in current tank showing signs of ich is the blue tang. It has had it several times but it doesn't seem to bother it. Fish in tank are.
1x Blue tang
1 x scopas tang
1 x six line wrasse
1 x flame angel
1 x emporer angel
2 x clown fish
1 x naso tang
1 x bristle tooth tang