Another Ich question

[MGB]

In trying to understand ich, I have a couple of questions:

If one fish in a system exhibits ich, does that neccessarily mean that all the fish in the same tank will eventually contact the disease, or is it possible that some fish can resist it. According to everything I read, once it's in a particular tank it will keep multiplying via any host fish available. If that's the case and its a parasite, why would it kill everything. As a parasite, it wants to maintain the host in order to survive itself. Is it possible that ich can exist in a tank at some level, only blooming on certain stressed, weak individuals, but not able to effect fish that are healthy and therefore resistant.
Also when it appears on the fish, what's the normal length of time before it detaches, can that be a little as a few hours and what is that dependant on.

Any thoughts appriciated, thanks MGB

 

[leebca]

Your reasoning, although sound, doesn't apply in the marine aquarium. I've conducted lab experiments and have dealt with this parasite since 1969. Let me explain.

In the wild, when a fish gets Marine Ich (Cryptocaryon irritans) the fish is free to swim around and away from the area it contracted the parasite. The parasite gorges itself, becomes 'pregnant' and drops off. The fish swims away from the cyst that releases the free swimming, infectious Theronts. So the fish has a chance to 'get away' from further infection.

By your reasoning, the parasite has indeed not killed its host. The parasite now looks for another fish who 'happens by' where the infectious Trophonts are.

See where I'm going? In the aquarium, the fish can't escape. The infectious stage keeps attacking the infected fish, living off of it. The fish can't 'get away' and keeps getting reinfected until it is overcome from the infestation, or by chance develops an immunity before it is killed.

Regarding the first question. . .The 'problem' with this disease is that not all 'spots' are visible to the human eye. This parasite actually prefers to reside in the fish's gills, where we can't see it. By the time we see the disease as spots on the fish's body or fins, the parasite could have gotten a good foothold.

The only way to overcome the infestation is to remove all fish and treat them to clean them of the parasite; let the tank go fishless for about 8 weeks, and return the clean fish to the display.

The MI imbeds itself on the fish and buries itself under the slime coating of the fish. This is one reason it can't be attacked by us -- it is protected by its host. This is the reason why a fresh water dip doesn't cure the fish. The MI engorges itself and drops off as a cyst. This has an average time of 4 to 10 days. BUT, the problem is that sometimes it was found to take a few hours or a couple of weeks. A big range. There are no absolutes. For instance, some cysts don't have to drop off at all! They can stick to the fish and release their Trophonts. Rare but possible.

What determines if the fish is infected has nothing to do with weakness of fish or parasite. It is just opportunity. Going back to the 'fish can't get away' scenario, the numbers of parasites keep multiplying until either the fish survives by chance, gaining immunity, or dies.

I have found that in a mixed (community) tank, about 4 to 10% can develop an immunity if they are strong, healthy, and either had some innate immunity developed in the wild, or 'luck out.' However, the ones that survived can still harbor the disease and the next incoming fish that has no immunity can suddenly lead to an explosion of the disease. During this explosion, the original carrier can actually die. It's again, the matter of numbers and opportunity.

In short, Nature has it all worked out -- in the sea -- not in an aquarium! In the aquarium, we humans have given this parasite an advantage over the fish they wouldn't normally have in the wild. The 'kindly parasite' becomes a killer in our aquariums. :rollface:

 

[FxdupCobra]

Very insightful as always Leebca. I have been researching this parasite for sometime of course not to the extent as you, but what confuses me is if it is a parasite and if it the fish (lets say a clown) has a thick slime coat then the ick cant attach. If it doesnââ"šÂ¬Ã¢"žÂ¢t attach it cant reproduce, if it cant reproduce then it will eventually die. Wouldnââ"šÂ¬Ã¢"žÂ¢t this mean that ick can be killed off as long as they donââ"šÂ¬Ã¢"žÂ¢t host on the fish? I know in the research I have read that the chances of the fish being able to resist the parasite is slim but possible. Is this true?

 

[leebca]

FxdupCobra,

Now you're getting into the biochemical abilities of the parasite.

The slime coating of the fish acts like a deterrent, but not protection. The infectious Trophonts actually have a chemical that can get through the slime coating to the fish's body. It is harder for the parasite to do this, then when infecting the more exposed tissues of the gills.

In the case of tangs, their coating is weak and their body is covered by a different mechanism which is practically NO deterrent to this parasite. That is why we see so many more tangs with this parasite.

For the above reasons, a healthy or sick fish is just as susceptible to the parasite. It's not a matter of will the fish get infected; it's a matter of how long the fish will survive after the attack. This survival aspect is the part related to fish stamina, health, diet, stresses, etc. Like computer hard drives: It isn't a matter of if they will fail; it's a matter of when they will fail. Infection (or drive failure) is inevitable when the parasite is in sufficient numbers.

As is common in Nature: When one organism has a defense, the enemy organism has a circumventing mechanism.

There is work being done along the lines you are thinking. For instance, what if we (humans) could artificially induce the fish coating to have an absolute protection against the parasite? It wouldn't be an immunity in the truest sense of the term, it would be a genetically or chemically induced 'shield.' But, you are correct: If the parasite can't infect a fish, the parasite dies. That is part of the basic definition of an obligate parasite.

Whenever you find yourself making an absolute statement in this hobby (like using the word "can't") then you usually can count on it being wrong, somehow; somewhere! Don't forget, there is no slime coating on the gills and the fish, swallowing so much water as the fish does, the fish has an increased probability of getting infected in the gills than on the body/fins. :rollface:

 

[MGB]

Hyposalinity question

Hyposalinity question

When performing hyposalinity for the treatment of ich, how does the low salinity effect live rock, I understand it will kill any invertebrates that happen to be living on or in the rock, but does it kill the good bacteria residing in and on the rock and consiquently impacting the biological filter for the tank, possibly drastically.

Also what are the effects of hyposalinity on coralline algae, can they survive it, or will it recced and die. Thoughts appriciated, MGB

 

[leebca]

The bacteria responsible for nitrification of the biological wastes in the aquarium are not killed by the hyposalinity treatment. That includes those that are on and in the live rock.

Unfortunately, these bacteria can be affected. The change in salinity usually puts the bacteria into a metabolic state of rest while they adjust to the new salinity. So, for a short time they may cease to function/eat/grow or they might just slow down in their waste handling 'duties.'

However, the hazard to putting LR through a hypo treatment is like you mentioned -- the death of the other organisms. It is many of these other organisms that make the LR, LR. Without them, the value of the rock drops down to the price and value of. . . base rock. This death will create a spike in ammonia. If you couple this spike with the (above mentioned) fact that the bacteria may stop processing waste, the water becomes deadly to the fish you're trying to treat.

During a hyposalinity treatment, you will have enough trouble trying to keep the pH high and stable. You don't need to wrestle with ammonia and nitrite spikes making the whole experience deadly or stressful for the fishes. Leave the LR in the display. OR if you must convert it to base rock, do that separately.

Coralline algae is pretty resilient. I have never heard that a hyposalinity treatment has killed them. Like the bacteria, they will probably hibernate for a while. I've had only small quantities of coralline go through a full 9-week hyposalinity treatment and survived. Truthfully, I couldn't tell if it grew or not during that time. If it did, it was not visible to the eye. So, I'm unsure if that is representative of all the types and variations out there.

Hope this helps! Ask if you have ?

 

[MGB]

Thanks for the info, I appriciate it. I'm trying to figure out in my head which would be the most desirable quarentine set up, unfortunately fish really respond well to an enviroment full of live rock, rather than a sterile plastic substitute. A compromise seams difficult, on the one hand a tank absent of live rock is more practicle for hyposalinity, on the other a tank full of live rock provides a less stressful enviroment, where acclimation is less stressful. Quite frustrating really.

 

[janakaybravo]

Sorry to jump in this thread, but I need an answer. How long can a fish stay in hypo, 1.009 safely? I have a blue tang that's been in 8 weeks and will probably keep him 12 weeks if that's ok.

 

[janakaybravo]

MGB, they'll be ok for 8 weeks in a sterile tank with pcv pipe. Mine just went through it. But the challenge like lee said is keeping the bio filter stable. Just get a big qt tank.

 

[MGB]

Jana, what do you call big, is 50 gal sufficient. What did you use for a bio filter. Please give details of your quarentine setup

 

[janakaybravo]

I have a 40 gallon qt tank. My display is 120. It's very important to establish a bio filter before you add the fish. You do that by buying a filter for your qt. I got an aquafilter from Dr. Foster & Smith rated for 110 gal. I put the sponge in my sump of display and let it stay a couple of weeks. I had time because my fish were ok even though they had ich. The challenge is not losing your cycle. I took the sponge out and put in the qt filter. The ammonia needs to be near 0, the nitrite also 0. When the nitrates get close to 30, I do a 40 percent water change. You have to get the salinity to 1.009 to be effective. You can do that very quickly, see Advanced Aquarist. com January issue. Also Steven Pro has good qt article in sticky of fish disease on this forum on QT tanks. I have learned everything I need to know on this forum.

Also important is to measure ph every day to keep high, tends to drop at 1.009.

I know it's a lot of work, but the reward is an ich free tank. From now on, I'll quarantine everything 4 weeks, fish immediately into hyposalinity, inverts just 4 weeks to let any ich on them die. That's the only way to keep it away. I hate to look at my tank with ich on my fish!

I put my first group back in the tank today. They look great. Hope this helps.

 

[MGB]

Good info Jana. I have another question; about freshwater dips. How effective, percentage wise, are they at ridding the fish of ich. I'm presuming FW dips are not 100%, if they were it would simplify the quarentine proceedure. Then one could be assured the new fish had no parasites before entering the tank. It wouldn't stop the fish from getting reinfected in the new tank, if ich was present, but it might severely limit the introduction of ich, which wasn't apparent on the fish before purchase.

 

[janakaybravo]

My understanding from all the reading I've done is freshwater dips are not effective against marine ich, but may be for other diseases. The only sure way is to qt all new fish in hypo for 4 weeks. I know it's tough. But after your display is fishless for 8 weeks and any fish you put in is at 1.009 for 4 weeks after no spots showing, then you can be relatively sure that no ich will enter your display.

TerryB has good article in Advanced Aquarist online magazine January issue about putting the new fish into hypo at 1.009 without much acclimation, just temp and ph. Go to advanceaquarist.com for his first article in a series. Feb issue he promises more detailed info to come.

 

[leebca]

I'm not usually on line after 7 p.m. Pacific Time.

Going back to where I left off. . .MGB: Your acting like the fishes have enough intelligence to be happy or sad; to know the difference between a real or plastic environment. I wouldn't make these assumptions!

Ever seen those plastic "sewer pipe" decorations? They come in all sizes. I use them not only in my QT, but I've worked them into my displays. The fish 'love' them! They swim in one hole and swim out one of three other holes. I use them to create 'tunnels' from the front to back of my LR and even into other spaces within the LR. In the QT the fish swims into it and pokes its nose out of the upper pipe to watch me put food in the tank. It's all they need.

In my displays, every old fish tries to make the sewer pipe decor its home/territory, but all the fish use the 'highways' that no fish can claim the pipe! And when things get tough (scary), three or four fish cram into the same pipe for safety!

Of course the fishes will be 'less stressed' in a larger tank, but your QT is not about size, it's about function and it's temporary. Providing hiding places is all that's needed. I've quarantined more than 650 fishes over the last 35 years. It's not frustrating to me.

 

[leebca]

Jana,

Studies have shown that food fish in hyposalinity can live an extremely long time. It has been projected by some reliable scientists that they and oranamental marine fishes could live indefinitely at low salinity. Where things quickly go wrong is maintaining stable water parameters at the right levels while keeping the salinity low. Lowering the salinity upsets Nature's balance with the dozens of ingredients in the water.

So 12 weeks in hypo is okay, if the hypo is being controlled for water quality.

 

[janakaybravo]

Thanks Lee! I can relax now and enjoy my fishes and test my water and test my water and test my water.

 

[MGB]

Lee,
I guess I was presuming that fish such as a dwarf angel feel far more comfortable in a rock enviroment that somewhat approximates its natural enviroment, rather than a plastic tube creation in an otherwise bare tank. I could be wrong, but I guess its hard to quantify the effects and consiquences of either set up on a particular fish. That given and what we already accept and know about salt water fish, is that they seam to prefer enviroments that mimic their natural ones.

 

[leebca]

Are you sure you're just not putting human emotions onto a fish? What do we know about what they prefer? I assume if they prefer anything it would be to have been left where they came from. A fav saying of mine: "If fishes had wishes, there'd be no fishes."

Assuming water quality is where it belongs:
1) A frightened fish (and newly acquired angels are usually in that category) is looking for a place to hide. Does it care if it's rock or plastic?

2) The next thing the fish needs is food. It recognizes the place it came from as to how to acquire/find its food. That could be rock or substrate or open water, or any combo. If an artificial rock has food on it, does the fish care if the rock is granite, lava, sandstone, or plastic? If I drop an artificial clam on the half-shell (and I have) laced with meaty prepared food the angel loves into the QT, does the angel care if the clam shell is real or plastic? I have fed Moorish Idles on a dinner plate. After a few weeks of this, they would go berserk trying to get to the plate (happy?) when the plate entered their tank.

3) Once 1) and 2) are secured, the next thing the fish wants is to procreate --- make more little fishes. Aquarists are coming along in that area, but we aren't there yet for all the angels.

At what point would you say the fish is happy, or unhappy? No matter how hard we try, we can't duplicate its natural environment. We can only mimic it. Can we truly remove absolutely all stress on our fishes?

An argument is given that fish should not be quarantined because they are not happy in the QT. But how many fish, released into their 'comfortable' display just hide until they die? Happy fish? One distinct advantage our cages have is (if we do it right) to have no disease or predators there, adding years to the average lifespan of the fish.

I know where you're coming from MGB. I do sympathize though the above may seem hard-hearted. But I believe. . .

If we as aquarists have taken the step to remove a fish from its natural environment, then the first step to settling it into our artificial homes is to acclimate it and, at the same time, to protect our acclimated fishes.

The QT doesn't have to be stark: You can put in artificial anything into the QT -- you can put in silica based sand and substrates (just no carbonates) I don't have any indication that the fish cares about what the environment is made out of, so long as items 1) and 2) are at a minimum, satisfied. In fact, as I noted in a previous post, I have fish in my display which prefer to stay in or near the plastic sewer pipes, although there is plenty of LR for them to choose from. Hmmmm

:rollface:

 

[MGB]

Your approach undoubtedly has strong proven evidence, however I feel it's a little symplistic to assume that just because the safe shelter and food requirements of a newly aquired fish are met that that in itself should allow acclimation without any major problems. How well or quickly a fish acclimates to captivity is dependant on more than safe shelter and available food.

My train of thought has nothing to do with trying to understand wether a fish is "happy" or "sad", I'm thinking what would be the "best possible" enviroment that illicits an already stressed fish, from the process of capture and travel, to resume its natural behavior. I'm sure you'll agree that enviroment must play a role in this responce, all animals, including fish must have behaviors that are triggered by their enviroment, in order to survive.

I agree that some species are obviously quicker at adapting to new enviroments than others, however from all the anactdotal evidence within the hobby, it would appear that a more "natural" enviroment can have a significant effect on the success of acclimation by certain species. Many marine fish come from extremely specialised niches wouldn't it be logical to attempt to mimic such enviroments in order to lessen the trauma of acclimation. Reef keeping has come a long way understanding the needs of many corals, however it seams fish keeping has still got a ways to go.

 

[TerryB]

I think it is important to try and imulate the natural environment to the best of our abilities. Do I think the non-coral eating species care whether the corals in the tank are real or artifical...no. However, recreating the natural habitat is helpful to a point. Fish that sleep in fine sand should be provided with it. Fish that perfer low lighting or caves to get out of direct light should have them. Fish that comes from an environment with moderate water current may be stressed in a tank with violent current. Fish that come from a turbulent environment may need a lot of water current because it contains more oxygen. Fish should also be provided with a diet that is as close as possible to what they eat in the wild.

Terry B