Can low salinity hide disease not prevent?

[exnisstech]

Background. A couple of years ago I bought an imperor angel that looked perfectly healthy. By passed QT and acclimated it and placed it in the display. I no I shouldn't have. The fish came from a tank that had a salinity of 1.015. Two days after adding the angel the tank broke out with velvet. The angel was the only new addition in almost a year. I no longer buy fish there.
Fast forward. A little over a week ago I bought a powder brown tang and an orchid dottyback. I've been buying fish at this store for a while. Salinity was always at least over 1.020. We'll when I got home and checked the salinity was 1.017. Did acclimation and placed the fish in QT. I slowly over a few days ramped up the salinity to 1.024 and began ramping up copper. 2 days after reaching 1.024 salinity fish are covered in ich. I got copper up to 2.1 (tested with Hanna) over 2 days and this morning both fish are dead and covered in what appears to be severe ich. Tank was an instant cycle using live rock and seeded sponges from a spare system I keep running. No presence of ammonia. No heavy breathing. Plenty of oxygenation from a air powered sponge filter and a hob that had the water falling a few inches before reaching the water and also a nano power head in the tank. There are even asterina stars on the glass.
Vendors say they run low salinity to prevent disease. I'm wondering is it possible that these lower salinity levels actually just hide the disease which then rears it's ugly head when salinity is increased to normal levels?

 

[vetteguy53081]

Background. A couple of years ago I bought an imperor angel that looked perfectly healthy. By passed QT and acclimated it and placed it in the display. I no I shouldn't have. The fish came from a tank that had a salinity of 1.015. Two days after adding the angel the tank broke out with velvet. The angel was the only new addition in almost a year. I no longer buy fish there.
Fast forward. A little over a week ago I bought a powder brown tang and an orchid dottyback. I've been buying fish at this store for a while. Salinity was always at least over 1.020. We'll when I got home and checked the salinity was 1.017. Did acclimation and placed the fish in QT. I slowly over a few days ramped up the salinity to 1.024 and began ramping up copper. 2 days after reaching 1.024 salinity fish are covered in ich. I got copper up to 2.1 (tested with Hanna) over 2 days and this morning both fish are dead and covered in what appears to be severe ich. Tank was an instant cycle using live rock and seeded sponges from a spare system I keep running. No presence of ammonia. No heavy breathing. Plenty of oxygenation from a air powered sponge filter and a hob that had the water falling a few inches before reaching the water and also a nano power head in the tank. There are even asterina stars on the glass.
Vendors say they run low salinity to prevent disease. I'm wondering is it possible that these lower salinity levels actually just hide the disease which then rears it's ugly head when salinity is increased to normal levels?

They run low salinity to reduce chance of infection, Hypo-salinity will reduce disease and control ich, Ramping copper is a no-no as doing so can allow the disease to gain resistance making it harder to treat given disease. Add partial doses and get to the full treatment level as soon as possible Copper doesn't work well until you get above 2 ppm, and then, it can take three days to slow/stop an infection.

 

[exnisstech]

They run low salinity to reduce chance of infection, Hypo-salinity will reduce disease and control ich

By control ich does than possibly mean suppress it not illiminate it?

Fish were showing signs of ich before I even started copper. I prefer to do observation and make sure fish are eating before medicating. They exhibited zero signs while at the store in 1.017 water. Spots did not appear untill salinity was raised in the QT. Same as the angle that brought velvet in. No signs at store salinity of 1.015 but as soon and fish was placed in salinity of 1.025 velvet appeared. Maybe it's just a strange coincidence.

 

[vetteguy53081]

By control ich does than possibly mean suppress it not illiminate it?

Fish were showing signs of ich before I even started copper. I prefer to do observation and make sure fish are eating before medicating. They exhibited zero signs while at the store in 1.017 water. Spots did not appear untill salinity was raised in the QT. Same as the angle that brought velvet in. No signs at store salinity of 1.015 but as soon and fish was placed in salinity of 1.025 velvet appeared. Maybe it's just a strange coincidence.

lower salinity will curb but not prevent it from overtaking a fish or reproduction od cysts. .
observation is as it implies- observe fish for any signs that show up, but then warrants treatment. You may or may not see signs at store initially but most stores share on filter system and if one tank has an issue, other tanks likely to contract the same issue. Assume even when you see no sins that the fish has something, hence reason for quarantining.
Getting to salinity of 1.025 is where ich and velvet thrive best and other than copper treatment is TTM or hyposalinity

 

[MnFish1]

By control ich does than possibly mean suppress it not illiminate it?

Fish were showing signs of ich before I even started copper. I prefer to do observation and make sure fish are eating before medicating. They exhibited zero signs while at the store in 1.017 water. Spots did not appear untill salinity was raised in the QT. Same as the angle that brought velvet in. No signs at store salinity of 1.015 but as soon and fish was placed in salinity of 1.025 velvet appeared. Maybe it's just a strange coincidence.

In answer to your direct question - I would surmise that low salinity at the LFS (but not at the level recommended for hypo salinity - 1.009) - that some parasites would be held at bay rather than kill them.

It is kind of confusing whether you're asking about your new fish - and what to do - or just the question about hypo salinity?

 

[MnFish1]

PS - I'm not sure that the LFS is using hypo salinity to keep parasites at bay - but rather to save money on salt. Similar to using 'low dose copper', using hypo salinity to help manage parasites (at partial levels) should be avoided if possible.

 

[exnisstech]

It is kind of confusing whether you're asking about your new fish - and what to do - or just the question about hypo salinity?

Really just wondering if it's possible the disease could be suppressed and not show signs while at the lower salinity then signs appear after the fish is placed in normal salinity. New fish have passed.

PS - I'm not sure that the LFS is using hypo salinity to keep parasites at bay - but rather to save money on salt. Similar to using 'low dose copper', using hypo salinity to help manage parasites (at partial levels) should be avoided if possible.

I've always thought they keep it low to save salt as well even though they say it's for disease prevention. I typically do not buy from stores that keep their salinity low. This store where I bought the fish use to not keep low salinity in the past but recently added a lot of new tanks so maybe they need to save money now. I have one more lfs left that keeps fish at 1.025 and even there I will only buy fish from the tanks that contain coral and inverts because I believe they keep copper in the other tanks.

 

[MnFish1]

Really just wondering if it's possible the disease could be suppressed and not show signs while at the lower salinity then signs appear after the fish is placed in normal salinity. New fish have passed.


I've always thought they keep it low to save salt as well even though they say it's for disease prevention. I typically do not buy from stores that keep their salinity low. This store where I bought the fish use to not keep low salinity in the past but recently added a lot of new tanks so maybe they need to save money now. I have one more lfs left that keeps fish at 1.025 and even there I will only buy fish from the tanks that contain coral and inverts because I believe they keep copper in the other tanks.

I do the same - if the fish are not with inverts, I don't buy them. In theory, inverts should also not be kept in hypo salinity.

 

[Jay Hemdal]

Background. A couple of years ago I bought an imperor angel that looked perfectly healthy. By passed QT and acclimated it and placed it in the display. I no I shouldn't have. The fish came from a tank that had a salinity of 1.015. Two days after adding the angel the tank broke out with velvet. The angel was the only new addition in almost a year. I no longer buy fish there.
Fast forward. A little over a week ago I bought a powder brown tang and an orchid dottyback. I've been buying fish at this store for a while. Salinity was always at least over 1.020. We'll when I got home and checked the salinity was 1.017. Did acclimation and placed the fish in QT. I slowly over a few days ramped up the salinity to 1.024 and began ramping up copper. 2 days after reaching 1.024 salinity fish are covered in ich. I got copper up to 2.1 (tested with Hanna) over 2 days and this morning both fish are dead and covered in what appears to be severe ich. Tank was an instant cycle using live rock and seeded sponges from a spare system I keep running. No presence of ammonia. No heavy breathing. Plenty of oxygenation from a air powered sponge filter and a hob that had the water falling a few inches before reaching the water and also a nano power head in the tank. There are even asterina stars on the glass.
Vendors say they run low salinity to prevent disease. I'm wondering is it possible that these lower salinity levels actually just hide the disease which then rears it's ugly head when salinity is increased to normal levels?

Velvet (Amyloodinium) is not controlled by hyposalinity. It has been recorded in fish as low as 4 ppt, which is lower than reef fish can tolerate.

Marine ich, Cryptocaryon, is not eliminated until the tank is taken to a specific gravity of 1.009 and held there for a period of time (I use 30 days, some people go 21). So a specific gravity higher than that can inhibit, but not eliminate marine ich.

That said, your fish dying in just four days (2 to bring up the SG and 2 to get the copper up?) is unusual to say the least. Copper should be ramped up faster, and it does take about three days to really work, but to see the fish outright die from ich in 4 days is odd - I wonder if something else was going on at the same time?

The Asterina starfish on the glass is weird - sometimes crustaceans can survive in copper for a bit of time, but I would not have expected a starfish to do so.....

Jay

 

[MnFish1]

Velvet (Amyloodinium) is not controlled by hyposalinity. It has been recorded in fish as low as 4 ppt, which is lower than reef fish can tolerate.

I meant to question this Jay (not you - but ask a question) - are there any other parasites that are controlled/killed by hypo salinity that will not kill the fish (I assume it SHOULD help with flukes?). Additionally, though velvet has been found - do you know if it multiplies and continues infection as quickly in a fish tolerable hypo salinity? Thanks

 

[Jay Hemdal]

I meant to question this Jay (not you - but ask a question) - are there any other parasites that are controlled/killed by hypo salinity that will not kill the fish (I assume it SHOULD help with flukes?). Additionally, though velvet has been found - do you know if it multiplies and continues infection as quickly in a fish tolerable hypo salinity? Thanks

Noga says Amyloodinium can cause active disease down to 3-4 ppt, but that isolates from the Red Sea tap out at 12 ppt.

Uronema actually thrives in brackish water.

Most flukes are controlled by hyposalinity, but there are some brackish water species that are not.

Brooklynella is a wild card - IDK about that. FW dips seem to help with Brook, but I don't know if hypo is effective.

Jay

 

[lion king]

I call this a dirty trick that many suppliers are guilty of, it causes many issues from the suppression of disease and parasites, to the complications that can occur in acclimation. When receiving a fish in low sg, below 1.020, I say brace yourself as you raise the sg. Also if you don't have an observation/qt tank you can adjust to match the sg of the bag, prepare a temporary transfer container to slowly raise up the sg, or this just becomes another risk.