Specific gravity and waterchanges in QT

[MarkW19]

I have a 15gal QT, and my SG is currently 1.021.

When I do a 50% waterchange, is it ok to put in new water that has an SG of 1.023, ie. half of the water will be an increase of 0.002?

 

[Atari]

So the final SG will be 1.022? Math hurts my head :?

I think it'll be fine.. what's in there?

 

[MarkW19]

Final SG will be 1.023 probably a bit lower as half of the water will be at 1.021 when the other is added!

Yellow long-nosed butterfly

 

[loganj]

I don't think you'll have any problems with a .002 change in SG. I would try to match the SG of the main tank as closely as possible before adding the butterfly though.

 

[MarkW19]

OK, thanks guys!

 

[steve-s]

Final SG will be 1.023 probably a bit lower as half of the water will be at 1.021 when the other is added!

1.021+1.023/2= 1.022

Lowering salinity is much less stressful on fish than raising it. Personally I would suggest not increasing salinity more than 0.001 each day.

Cheers
Steve

 

[MarkW19]

I've made a bit of a booboo with my waterchange water for my QT.

SG in QT now is 1.023, SG in new waterchange water is 1.021. This is water for a 50% waterchange.

Am I ok to add the water or should I put some more salt in and wait til tomorrow?

I'd rather do it now because ammonia and nitrites are JUST starting to be detected slightly.

 

[mr_tee0419]

Everything should be fine as long as you are between 1.020 and 1.025. Maybe add 1/4 or 1/2 now and some later. Less sudden change in SG would reduce stress.

 

[steve-s]

When dealing with a QT and only fish are present, a 0.001 downward movement in the SG is of no concern. The ammonia is more important. Fish can handle salinity changes downward much larger than that. Only be concerned if increased quickly, that they cannot tollerate well

Cheers
Steve