Salinity Math and appropriate movement for fish

[thelawnwrangler]

I am at 1.020 and I want to get to 1.025

Today I plan on doing a 5 gallon of 30 gallon water change.

5/30 * 1.025 = .1708
25/30*1.020=.85

New salinity is .1708+.85=1.0208

I will do another change in 2 days

Does that sound right / acceptable?

 

[Sk8r]

You'll go crazy trying to make it work that way, unless you're a mathematician. It's a lot easier to use kitchen chemistry and think like a cook. For most salt mixes, 1 precise half cup to one precise half gallon yields 1.024 salinity, which is reef salinity.

If you just top off evaporation with salt water instead of fresh over several days you will at some point get to your desired salinity. Remember that with fish in the tank, you can lower salinity rapidly in safety, but raising it too fast can kill them from osmotic shock.

 

[thelawnwrangler]

What do you think is to fast is .001 at once too much?

Based on first test it looks like math works

Unsure if I did too much.

 

[thelawnwrangler]

sounds like raising salinity is the monster internet search just says slow.

Thanks for explanation skr I would have thought up or down was the same


seeing no more than .001 so I probably pushed it. ugh

 

[Nniemeyer]

Isn't it 1/2 cup per gallon, not per 1/2 gallon?

 

[CStrickland]

Isn't it 1/2 cup per gallon, not per 1/2 gallon?

Yes, at least for the salt I use.

 

[sticky polyps]

Yea sk8er, we know u meant to say half cup per gallon..;-)

And for the original post, if it is just fish I would not be worried about bringing it up all the way within a few hours.. Could be wrong though. GL

 

[sticky polyps]

Oh, just read the other half of sk8r's post... I would do that..! Definitely just top off with salt water instead of fresh. Can't believe that didn't come straight to my mind, have done this many times with my reef just to fine tune the salinity.

 

[thelawnwrangler]

Yea sk8er, we know u meant to say half cup per gallon..;-)

And for the original post, if it is just fish I would not be worried about bringing it up all the way within a few hours.. Could be wrong though. GL

scary math because I think using SG vs PPT is the wrong approach. My water change might have been slower than topping with salt water.

I top off about 2 quarters a day so .5/30 X 1.025 would be addition of .0017 vs the increase of roughly .001 or .0008 I did today.

ATO though slowly increasing through day is probably most ideal