This is my first article on this forum so I hope you enjoy it and benefit from it.
One of the most common diseases in saltwater that we usually face is Cryptocaryon Irritans or commonly known as Marine Ich. There are few treatments that pop to mind, Copper, Chloroquine phosphate (CP), Tank Transfer Method (TTM), or Hyposalinity.
Hyposalinity was always somewhere there on the list, some say it works, some say they had no success with it, so I decided to do some research to find a solution once and for all, does it work or no. Note that Hyposalinity is claimed to work only on marine ich and not any other type of parasites. So if you have velvet, fluke, brook, etc.. use the appropriate treatment and totally forget about hypo.
Spoiler Alert: It does not work (I know some people will disagree, but hey experiments proved it, and also you might be lucky to not have the resistant strain), use one of the guaranteed methods to treat ich: Copper, CP, TTM. Always observe fish for few weeks after treatment before placing in Display Tank. Hypo is still beneficial for fish and you can run tank on it (FO/FOWLR or QT only) although not to extreme ranges, will do an article soon about that .
Introduction to hyposalinity treatment:
From the name you probably guessed what is meant by hyposalinity treatment, or hypo for short. Basically, you want to treat the fish by lowering the salinity to extreme values where fish can still survive it but parasites won't. Its not clear at which salinity it’s stressful for fish or start affecting it, but people commonly run it at 1.008-1.013 (11-17 ppm).
So how does it work?
Hypo will only work on ich (and not all strains of ich). Unlike fish, the Crypto. are not capable of osmoregulatory, that means that as salinity drops, fish will adjust and balance the salts in their bodies so they don’t swell up, but the crypto cant, so hyposalinity will cause them to absorb the surrounding water to a point where they will pop and die, that’s why its necessary to lower the salinity enough to allow the parasite to absorb as much water as possible to make this happen.
That makes sense, so why it isn’t an effective treatment? Low salinity will cause the parasite to swell and pop, problem solved, correct?
Well, in most cases it will work, but as you know Ich has many strains, unfortunately, some are capable of swelling up and not popping at these ranges, they will still be able to reproduce and continue the life cycle normally. This study shows that fish were collected from fish farm infested with ich. The study utilized hypo and hyper as a method of treatment. I suggest you read it as it has some useful information, but here is what they found. They tested fish with different ranges of salinity and they found out that ich can survive at salinity of 15 ppm (1.011) but didn’t survive the 10 ppm (1.007) sality solution. So, somewhere in between is the sweet spot for killing ich right? Regrettably, no. Other than the fact that this is not a safe zone to place the fish at, another more recent study found out that crypto can survive even lower salinity levels. If you read this study you will found out that ich can survive salinity levels as low as 5 ppm (1.004). You definitely don’t want your fish to be exposed to this low level of salinity as it will most likely die. Note that this is Crypto. (Marine Ich), not to be confused with Ichthyophthirius multifiliis (Freshwater ich). This is another article that explains the recent study and is a good read overall.
You can also google hypo treatment failing, believe me you will find a lot of topics where people tried hypo and ich pops back again.
Ok, so hypo is not effective treatment, but many people had success with it how?
They might be lucky and had the strains that died at the hypo levels they had. Crypto. has a lot of strains, and each strain has resistance against a parameter or two. Similar to the strain that can survive 76 days in fallow tank, another strain can survive at lower salinity, it's simply evolution taking its course. Another possibility is that it is ich management instead of ich eradication. Ill be adding another topic soon about the benefits of hypo, but basically it can boost immunity and decrease stress, so no ich is visible.
So this concludes the hypo treatment. As you know hyposalinity is not 100% effective against ich, it is better to treat with other more effective methods like copper, CP, or TTM. Ich has been found at salinity levels as low as 5 ppm, making it impossible to treat with hyposalinity. Ill be posting soon another thread about benefits of hypo, after all it might be beneficial, and not only for ich but probably for other diseases too.
Hope you enjoyed the thread and learned something, and happy reefing
One of the most common diseases in saltwater that we usually face is Cryptocaryon Irritans or commonly known as Marine Ich. There are few treatments that pop to mind, Copper, Chloroquine phosphate (CP), Tank Transfer Method (TTM), or Hyposalinity.
Hyposalinity was always somewhere there on the list, some say it works, some say they had no success with it, so I decided to do some research to find a solution once and for all, does it work or no. Note that Hyposalinity is claimed to work only on marine ich and not any other type of parasites. So if you have velvet, fluke, brook, etc.. use the appropriate treatment and totally forget about hypo.
Spoiler Alert: It does not work (I know some people will disagree, but hey experiments proved it, and also you might be lucky to not have the resistant strain), use one of the guaranteed methods to treat ich: Copper, CP, TTM. Always observe fish for few weeks after treatment before placing in Display Tank. Hypo is still beneficial for fish and you can run tank on it (FO/FOWLR or QT only) although not to extreme ranges, will do an article soon about that .
Introduction to hyposalinity treatment:
From the name you probably guessed what is meant by hyposalinity treatment, or hypo for short. Basically, you want to treat the fish by lowering the salinity to extreme values where fish can still survive it but parasites won't. Its not clear at which salinity it’s stressful for fish or start affecting it, but people commonly run it at 1.008-1.013 (11-17 ppm).
So how does it work?
Hypo will only work on ich (and not all strains of ich). Unlike fish, the Crypto. are not capable of osmoregulatory, that means that as salinity drops, fish will adjust and balance the salts in their bodies so they don’t swell up, but the crypto cant, so hyposalinity will cause them to absorb the surrounding water to a point where they will pop and die, that’s why its necessary to lower the salinity enough to allow the parasite to absorb as much water as possible to make this happen.
That makes sense, so why it isn’t an effective treatment? Low salinity will cause the parasite to swell and pop, problem solved, correct?
Well, in most cases it will work, but as you know Ich has many strains, unfortunately, some are capable of swelling up and not popping at these ranges, they will still be able to reproduce and continue the life cycle normally. This study shows that fish were collected from fish farm infested with ich. The study utilized hypo and hyper as a method of treatment. I suggest you read it as it has some useful information, but here is what they found. They tested fish with different ranges of salinity and they found out that ich can survive at salinity of 15 ppm (1.011) but didn’t survive the 10 ppm (1.007) sality solution. So, somewhere in between is the sweet spot for killing ich right? Regrettably, no. Other than the fact that this is not a safe zone to place the fish at, another more recent study found out that crypto can survive even lower salinity levels. If you read this study you will found out that ich can survive salinity levels as low as 5 ppm (1.004). You definitely don’t want your fish to be exposed to this low level of salinity as it will most likely die. Note that this is Crypto. (Marine Ich), not to be confused with Ichthyophthirius multifiliis (Freshwater ich). This is another article that explains the recent study and is a good read overall.
Full article here.“More recently, studies have demonstrated different salinity tolerances among strains of Cryptocaryon. Yambot (2003) described one Taiwanese outbreak occurring in sea bream Sparus sarba at a salinity of 5 g/L, and another outbreak in sea perch Lates calcarifer occurring at a salinity of 10 g/L. These two strains were successfully propagated in the laboratory at 7 and 10 g/L, respectively, and are well below previously documented preferred salinities.”
You can also google hypo treatment failing, believe me you will find a lot of topics where people tried hypo and ich pops back again.
Ok, so hypo is not effective treatment, but many people had success with it how?
They might be lucky and had the strains that died at the hypo levels they had. Crypto. has a lot of strains, and each strain has resistance against a parameter or two. Similar to the strain that can survive 76 days in fallow tank, another strain can survive at lower salinity, it's simply evolution taking its course. Another possibility is that it is ich management instead of ich eradication. Ill be adding another topic soon about the benefits of hypo, but basically it can boost immunity and decrease stress, so no ich is visible.
So this concludes the hypo treatment. As you know hyposalinity is not 100% effective against ich, it is better to treat with other more effective methods like copper, CP, or TTM. Ich has been found at salinity levels as low as 5 ppm, making it impossible to treat with hyposalinity. Ill be posting soon another thread about benefits of hypo, after all it might be beneficial, and not only for ich but probably for other diseases too.
Hope you enjoyed the thread and learned something, and happy reefing
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