hyposalinty!!

jbird0420

Active member
I have a huge ich outbreak in my 225 display tank.

What's the best way to lower my salinity in the tank without shocking or stressing the fish out? And what ppm does the water need to be at to be affective???

Thanks for the help!
 
s.g. needs to be 1.009 for a minimum of 10 weeks

I did this for 3-4 months in a QT tank, ich came back. I have a low-salinity-tolerant version of Ich, I believe. yes, i confirmed low salinity with a freshly-calibrated refractometer for 3+ months.
 
Should I slowly slower it over a few days? I got a 35g trash can of fresh RO/di ready to go.

And is it safe for the fish at such a low salitnity level 1.009??

Thanks for the help!! :)
 
Thanks for the info and help guys! I did a 30g water change. Brought the SG from 1.024 down to 1.019. Used up all my rodi product water. I'm making more product water now, should be complete in about 10hrs.

Ill do another water change to bring it down to 1.008sg
 
hypo will kill all inverts and all coral

you should only decrease Specific Gravity by 2 or 3 points per day, maximum, or the fish will be harmed/dead.

1.022 --> 1.019 day one
1.019 --> 1.017 day two

etc
 
Gotcha! It's a Fish Only tank with about 150lbs of LR and LS.


hypo will kill all inverts and all coral

you should only decrease Specific Gravity by 2 or 3 points per day, maximum, or the fish will be harmed/dead.

1.022 --> 1.019 day one
1.019 --> 1.017 day two

etc
 
ummm.... Actualy you only change salinity by .003 per day when going back UP, not when going down. You can hit your 1.008 in two days with no problems, 3 days is ok too. Fish tolerate the lower salinity very well, in fact it is easier for them to osmoregulate, and many institutions that maintain their tanks at hypo, introduce them without much acclimation whatsoever.

Going back up is another story. Since they have to expend more energy to omsoregulate at the higher salinity, we should make those increments very slowly.

Hyposaline conditions will kill inverts (snails, crabs, worms, etc.), therefore it is recommended to do so in a QT. If you do not have inverts, and don't mind losing your live "critters" in your sand bed, and live rock, then you could do this in your display tank. Your biological filtration will take a short term hit, but will come back in full force. You should be ready for large water changes when this happens.

You should get to your target salinity in 2-3 days.

SV
 
You need to be extremely careful here b/c you could very well kill all of your fish in the system if you do hypo in the display. As indicated, a great deal of fauna will die when the salinity gets low and result in a potential major ammonia spike. How significant (both in intensity and duration) of the resulting ammonia spike will largely depend on how much fauna (small life) you have in the system, or in other words, how "live" is your rock and sand. If you do not eliminate the ammonia timely (water changes, ammonia binder, bacterial additions), all of your fish will die. Sometimes you are able to keep up with the ammonia in this context, and sometimes you cannot. There is no way to really accurately predict whether you can keep up with the ammonia other than a vague estimate as to how much fauna you have in the system. At minimum, you need to carefully monitor the tank constantly during the first week of hypo and respond accordingly to ammonia to avoid disaster. Of course, this will involve constantly testing for ammonia with an accurate test kit.
 
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I found this interesting

During the study, fourteen 40-gallon tanks connected to a common filtration system at Kollman's dealership were run at 15 ppt salinity (1.011 SG), while sixteen other 30-gallon tanks, connected to their own separate filtration system, were maintained at normal salinities of 27-30 ppt (1.020-1.022 SG) and served as the control group for the experiment (Kollman, 1998). Both systems had identical filtration and were maintained at the same temperature (between 79ร‚ยฐF-80ร‚ยฐF), Kollman, 1998.
The test period ran continuously from 1994 to 1997, during which time marine fish from the Red Sea, Caribbean and throughout the Indo-Pacific were maintained in both systems (Kollman, 1998). Whenever fish arrived from wholesalers or transshipments, they were divided evenly between the low salinity and the normal salinity (control) system with no acclimation procedures whatsoever (Kollman, 1998; Giwojna, 2003). No differences in behavior were observed between the fishes in the two systems during the trial period.
The results of the three-year study were dramatic and conclusive. Outbreaks of Amyloodinium, Cryptocaryon, turbellarians, and monogenetic trematodes were simply not seen in the low salinity system, and periodic microscopic examinations of skin scrapings and gill clippings confirmed that none of the parasites were present (Kollman 1998). On the other hand, the normal salinity control system continued to have periodic outbreaks of all the above parasites. Furthermore, infected fish from the control system were cleared of their parasites within a few days if transferred to the low salinity system (Kollman, 1998).
Kollman found the low salinity system reduced his previously high mortality rates and that his dealership was able to greatly reduce chemical treatments and subsequent overdoses (Kollman, 1998). He concluded that a salinity of 14 to 15 ppt (1.010-1.011 SG) was an effective treatment level to which fish can be immediately transferred with no special acclimation procedures (Kollman, 1998).
Although the rapid turnover of specimens at his dealership prevented him from reaching any definitive conclusions about the long-term effects of low salinity on marine fishes, Kollman noted that several fish were maintained in the system for well over a year with no ill effects, and that a Red Sea Angelfish (Pomacanthus maculosus) thrived in the low salinity system for three-and-a-half years (Kollman, 1998)! Likewise, as indicated in the illustrations for this article, a number of exotic fish in Travis Carter's experimental angelfish community tank have been thriving at a salinity of 15 ppt (1.011 SG) for nearly a year now. However, hobbyists should be aware that the long-term effects of hyposalinity are still unknown and poorly understood, and that it is not intended or recommended for long-term use in normal applications. The proper use of OST is to maintain the hyposalinity throughout the quarantine period for new arrivals, or the treatment period (i.e., 30-45 days) needed to clear up an outbreak of parasites, and then to very gradually return the salinity to normal levels.
 
Gotcha! It's a Fish Only tank with about 150lbs of LR and LS.

Watch your ammonia and/or nitrates!! Although it's fish only, there will be critters on your live rock and substrate, and these will all die off. Your nitrosomas and nitrobacter should survive, so your ammonia spike may not be as bad, but then you'll get a huge nitrate spike. I did hypo on a 110 gal fish only with live rock and substrate, and I got a HUGE nitrate spike, and found all kinds of dead critters on my filters. Here's a link to what happened, post# 24: http://www.reefcentral.com/forums/showthread.php?t=1892446
 
Palting, I enjoyed your link.

Have you treated each new fish so far in QT with hypo? I'm debating this when I set up my new tank next spring. Just putting each new fish through hypo whether they seem infested or not. Of course not starting until they are eating well.
 
I stand corrected - raising S.G. is the critical point... I remember that now. It's been over a year since I ran my hypo experiments. Sorry.
 
Palting, I enjoyed your link.

Have you treated each new fish so far in QT with hypo? I'm debating this when I set up my new tank next spring. Just putting each new fish through hypo whether they seem infested or not. Of course not starting until they are eating well.


Although not addressed to me, I will chime in anyway since I have a strong view on this topic.:D

I firmly believe that every fish should be profolactically treated for parasites (I prefer cupramine and prazipro as opposed to hypo for the reasons described in the below link) whether or not a fish shows any signs of parasites. Although I do not have the link handy, I have read an article which opined that approximately 1/3 of all fish sold retail have a parasite, and therefore, the chances are good that if you purchase multiple fish you will eventually have to deal with a parasite. The most common reason quarantine fails is that parasites are often missed during during quarantine. It is not uncommon at all for a low level infestation to exist on fish in quarantine which is not discovered. Fish are then introduced to the display and infect the display and all fish therein. As you know, once a display gets infected, it is a real pain to remedy, and fish losses often occur. Quarantione without profolactic treatment for parasites is imo highly unreliable and often ineffective. Plus, if you profolactically treat you can often keep quarantine to under 4 weeks (if you go the cupramine/prazipro route) which is imo much less stressful on fish b/c quarantine facilities are usually on the smaller side with poor filtration which causes a great deal of stress on fish. The sooner one can get fish out of unduly undersized and poorly filtered quarantine system the better imo.

http://www.reefcentral.com/forums/showthread.php?t=1950458
 
As posted (by Stuart and others) your main challenge during hypo in your main DT will be keeping up with your ammonia spike that will inevitably occur. Your biological filtration within your sand bed, and live rock will take a sudden hit and lay somewhat "dormant" while adjusting to the new conditions. For some folks, this dormant stage is quick, while others it is much longer. During this time you need to have a lot of water, and Amquel or Prime available to detoxify your ammonia. One item of interest is that many test kits will give you a false "high" reading while using common test kits, even though your ammonia may not be at toxic levels. I have found that the API test kits are notorious for this. Find one that is not affected by these detoxifiers.

Once your live critters die off, you will overcome your biological filtration, since your fauna is normally in balance with the "typical" load of your system. With your inevitable die off, your biological filtration will likely over react, and a bacteria bloom could result. All of this should stablize in 2-3 weeks, where a good balance of nutrient load / fauna will be established.

During this 2-3 weeks you will need to be extremely dilegent in monitoring ammonia, and pH. In dilluted hyposaline conditions the ability to buffer (alk) is lessened, therefore it is difficult to maintain pH. You will need to buffer with baking soda (not marine buffers - they require NSW conditions to work). You could bake your baking soda at 350 degrees for 20 minutes to make a stronger pH additive. Mix this powder with DT water or top off to maintain pH.

Once this treatment is over, and after you raise your salinity back up, you can re-seed your system with live sand / live rock (QT'd) to re-establish what you lost in die off.

SV
 
Palting, I enjoyed your link.

Have you treated each new fish so far in QT with hypo? I'm debating this when I set up my new tank next spring. Just putting each new fish through hypo whether they seem infested or not. Of course not starting until they are eating well.

Yes, I do and will QT and treat all fish. You can not tell if a fish has Ich, even if they seem healthy for a month or more. My experience has taught me that. I prefer hyposalinity since I have done it successfully, and am comfortable with it.

If I have new live rock, or coral on a rock, I QT and leave them in a fishless environment for 6 weeks as well :).

BTW, most of the literature will say that you lose your beneficial bacteria with hyposalinity, as stated by the other posters above. That has not been my experience. Although the inverts and critters in my sand and rock died, the beneficial bacteria in my cannister filter and wet/dry with bioballs survived and converted all that dead stuff to nitrate. That's why I did not get an ammonia spike, but did get one heck of a nitrate spike.
 
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I would also add that in addition to using an ammonia binder like Prime or Amquel and water changes to control the ammonia spike caused from using hypo in the display, I have found that daily additions of a high quality live bacteria product, like biodigest, really help to control ammonia and stabilize the bacterial colonies which as pointed out above generally take a substantial hit during the first week or so of hypo. I have found that if possible you want to limit the water changes as much as possible with hypo because you inevitiably wind up geting your salinity too high and if elevated long enough will allow some ich to reproduce, thereby making hypo ineffective. As such, I much prefer managing ammonia with live bacteria additions and ammonia binders whenever possible.
 
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Korrine:

The information you posted about maintaining hypo salinity for extended periods of time is very interesting. Obviously, this could never work in a reef system and likely would not work with many species of inverts. The other thing that came to mind is that the problem with hypo is skimmer performance is really poor and often completely ineffective. I have found that you just cannot skim much during hyposalinity conditions, and therefore, water quality becomes a very serious challenge long term.
 
Stuart, it also won't work for some fish, namely cartilaginous fishes. Skimmers don't work this low. I tried it when adding salt to my last tank when I first filled it.

Thing is I'll only have a fish or two (3 when I do my McCosker's trio) in a 29g at a time. I'm thinking I may convert a few mollies to salt water and keep them in there when it's not in use to keep bacteria alive (will have a hob filter Aquaclear brand).
 
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