What should SG be in a QT tank

[jwheeler]

I'm setting up a 55g QT tank for my 180g display tank. What should the SG be for quarantine? I thought that it was supposed to be lower than normal.

[ReeferAl]

You should keep the QT at 16ppt which is a specific gravity of 1.010. This article has a good discussion of the hyposalinity method. While it can be used only when a fish is suspected of having ick it is best to "assume the worst" and prophylactically treat all new fish before introducing them to the display.

Allen

[jwheeler]

Thanks for the info, spent over an hour reading several articles found after that link. I thought I would need the QT tank to be running at all times, even when not QT'ing fish, but I guess that is not the case.

[yoboyjdizz]

i would keep your qt sg levels the same as the main only i would do hypo treatment if your fish so signs of illness. You don't want to treat a healthy fish...

[druce]

My QT was always the same SG as the main one - never tried the hypo, never liked the idea of it.

[ReeferAl]

I would DEFINITELY treat any fish I put into the QT with hyposalinity (other than elasmobranchs- sharks). If you have read the articles that would make the most sense.
Hyposalinity is very well tolerated by marine fish and in fact easier physiologically on them than NSW levels. Hyposalinity only becomes stressful when the salinity is lower than their own blood and tissues. At that point they have to do something their body is not made to do- excrete water and retain salt. Marine fish are adapted to do the opposite- excrete salt and retain water. It takes energy to do so against an osmotic gradient, so having the salinity just slightly higher than the fish's blood lessens the physiologic stress on the fish. It's an "osmotic break" for the fish that is already stressed by transport etc and it rids the fish of any ick infestation that might not be readily apparent. Basically, it's a no brainer.

The only real caveat is that you must raise the salinity back up slooowly, like over 5 to 7 days.

For those who haven't, I would strongly recommend reading the article I linked to and the related articles linked to it.

Allen

[druce]

well I'll be damned - when someone explains it like that, it's a little hard to argue.

Thanks Allen for the enlightenment.

Most of the articles I read said hypo never really did much to rid the fish of ick and that most of the ick parasites were "immune" to hypo and that's why I never tried it.

of course I'd think you were even more cool if you read from a GE PACS system at work

[yoboyjdizz]

Allen do you ever test the water your fish come in? Say its more closer to normal salt water levels do you still recomend throwing them in hypo right away? Shouldn't you start at normal levels and work your way down first?

[bureau13]

I personally don't like hypo, because it won't do you any good if your fish come in infected with velvet instead of ich. I've started using Cupramine in my QT, and so far there have been no ill effects from it (to compare, I've seen fish get pretty stressed out in hypo, all the professional recommendations notwithstanding).

jds

[ReeferAl]

Originally posted by druce
of course I'd think you were even more cool if you read from a GE PACS system at work

At our various sites we use 2 different PACS systems (soon to be 3- we cover 8 hospitals), but none is GE. Hospitals are too cheap.

Allen

[ReeferAl]

Originally posted by yoboyjdizz
Allen do you ever test the water your fish come in? Say its more closer to normal salt water levels do you still recomend throwing them in hypo right away? Shouldn't you start at normal levels and work your way down first?

I do test the water and most often it is at a SG of about 1.017-1.020.

I initially match the QT to the store water or a little lower. I then bring it down to 1.010 over a period of 8 to 24 hours, depending on starting SG and on my schedule. Certainly if it starts higher you could take it a little slower.

Allen

[ReeferAl]

Originally posted by bureau13
I personally don't like hypo, because it won't do you any good if your fish come in infected with velvet instead of ich. I've started using Cupramine in my QT, and so far there have been no ill effects from it (to compare, I've seen fish get pretty stressed out in hypo, all the professional recommendations notwithstanding).
jds

It is true that it won't have any effect on velvet or some of the other ectoparasites and none of the internal parasites. Still, it covers the most common problem, ick, and some others I believe.

IME, I have never seen a fish adversely affected by hypo. I have seen fish made worse by copper. It has a narrow therapeutic range. Too high and it is toxic to fish and too low and it is not effective against the parasites. It is still a reasonable approach for parasites that do not respond to hypo treatment. It can even be done in conjunction with hypo. I would only use copper in cases of actual infestation with an organism not responsive to hypo and not as a preventive treatment though due to the well-established toxicity of copper.

If you've had good experience with copper, then by all means go on using it. For anyone trying to decide how to proceed I would reccomend reading the articles before making a decision.

Allen

[ReeferAl]

Originally posted by druce
Most of the articles I read said hypo never really did much to rid the fish of ick and that most of the ick parasites were "immune" to hypo and that's why I never tried it.

From what I have read most of the strains of cryptocaryon (ick) that are resistant to hypo are temperate and not tropical strains, although that could change. Just like drug resistance, the best way to avoid selecting out hypo tolerant strains of ick is to treat low enough (SG-wise) and long enough. Partially treating a tank is the best way to eventually develop resistant strains. If that happens then the only non-toxic method left will be the "transfer method", which I believe is described in the article linked above.

Allen