hyposalinity in main display......question

[saltyESQ]

I have a 210g fowlr and just had a major ich outbreak.

My fish are just too large for a QT tank, so I have decided to slowly remove all the live rock and then remove the sandbed and then bring down the salinity to .009 for 6 weeks.
(I just purchased a new tank and plan on moving all the rock and sand to the new tank)

My question, how slowly should I take out the live rock so as to not cause an ammonia spike? ( I have about 270lbs of LR and 240lbs of LS)

how slowly should I take out the sand? I was thinking of just siphoning it out all at once.
Is there anything I should do to make sure I don't have an ammonia spike? how should I handle biological filtration?
I am planning on using my skimmer (asmg4x with sedra 9k used as a recirc pump and gate valve mod)

any advice would be appreciated.
my nitrates are 20ppm
(I think it was the blue tang that caused the ich outbreak as I just purchased him last week and didn't qt him)

my stock:
9" queen trigger
5"humu trigger
6" foxface
3" flag fin angel
3.5" maroon clown
6" blue hipp tang.

 

[brand26]

you wont have much skimming due to lower salinity, you need to leave a few live rocks and have something for bacteria to colonize before you take out most of the live rocks and sand but if i were you i would leave the sand in there too and just purchased new live sand for replacement when your done..i know its gonna cause ya but hey, who said this hobby is cheap. at least your fishes will be happy when all said and done also keep some ammonia detox and ready made water you're gonna need it as you will still have ammonia spike but at least it's not drastic to a point were it stresses your fishes. Have patient and
Goodluck!!

P.S. My fishes were in your situation too, and this is what i did
to eleviate the ammonia spike and all fishes made it through
and now happy at least i think they are

 

[stingythingy45]

I'm coming to the tail end of a hypo treatment now.
I've had my fish in QT tank with hypo since the first week of Dec.
The tank actually cycled during this time.I started with ammonia spike that I fought off with water changes and Amequel.
Like brand26 said,you need to leave some stuff to keep bacteria present in the tank.I moved a HOB filter from my display to the QT.
Mine was on a much smaller scale 55 gallon to a 20L.
IME,LS is really only alive because it has bacteria colonies living in it.The real question that needs to be answered here is:
Will SW bacteria colony survive Hypo down to 1.009 SG?
If it will then I mose definitely would leave the sand bed.

 

[julianp]

I've put live sand and rock (hardly any non-bacterial life forms in it) through hyposalinity (1.009 for 6 or 7 weeks). The bacteria was fine. I experienced no rise in ammonia, though with the skimmer's inability to function properly due to less surface tension, the nitrates in the tank rose over the 6 weeks from 0 to 15-20ppm.

I would take out 3/4 of the rock and place it in a heated container of regular specific gravity with a powerhead for 6 weeks minimum so that whatever cysts are on the rockwork can complete their life cycle and die off.

I'd say leave the sand in -- as disturbing it is going to kick up tons of nasty stuff into the water column and result in a huge mess. Unless there are thousands of bristleworms in it or something, you are likely not going to have much die-off.

Keeping at least 1/4 of the live rock (the pieces that have the least amount of visible life on them) is a good idea because it will give the fish places to hide and still function as a biological filtration system.

Then, just monitor ammonia daily and nitrate weekly for 6 weeks after the last cyst has disappeared from the fish. Make sure to keep some Amquel or something handy in case there is any ammonia spike and do regular water changes. After bringing SG back up to 35pt/1.026 or wherever you normally keep it, put the rock back in.

You'll probably experience an algae bloom during that time due to elevated nutrient levels from running skimmerless. As long as no ammonia is seen, it shouldn't be anything to worry about, though. My tangs seemed to enjoy the extra algae to graze on if anything.

Disclaimer: Not necessarily the "correct way".... just my own experience.
Good luck!,
-Julian

 

[cthetoy]

Any updates? How are your fish doing?