Amount of salt

[the_bandit]

If I am doing a 5g water change, how many cups of salt should I add? Ive been adding 2 and 1/2 and that is really bring my salinity up. 1.028 was my latest reading.

 

[rlablan]

Well I/O salt, and reef crystals is 1/2 cup per gallon. The type of salt you have should tell you what the correct amount is.

 

[meowzer]

Do you test the salinity of your new water before you put it in the tank?
Then if it is too high add more ro....

 

[the_bandit]

I use Coralife salt. It says add 1/2 cup for every gallon but that is too much. Would adding 2 cups be enough?

 

[louti]

1/2 a cup per gallon is just a ballpark. You need to measure the salintity and either dilute it with freshwater if it's too high or add more salt if it's too low. Your salinity is kinda high too, so you need to do a water change with lower salinity water, maybe 1.022-1.023.
Add two cups and see where you are at.

 

[nycbob]

u should be testing ur sg with a hydrometer or refractometer. adding salt by cup amount is never a good idea. if ur main display tanks sg is 1.028, perhaps the new water u r adding should hv lower sg.

 

[meowzer]

Originally Posted by The_Bandit
http:///forum/post/3172530
I use Coralife salt. It says add 1/2 cup for every gallon but that is too much. Would adding 2 cups be enough?
Yeah...when I mix mine, I test the salinity....if it is too high...I just add a little more ro until it is where i want it

 

[mkroher]

Originally Posted by nycbob
http:///forum/post/3172539
u should be testing ur sg with a hydrometer or refractometer. adding salt by cup amount is never a good idea. if ur main display tanks sg is 1.028, perhaps the new water u r adding should hv lower sg.
I'm willing to bet that if he does a 5gal water change with fresh water, he'll probably drop to 1.027.
I did hypo on a 29gal, and it took 3gal water changes of fw to lower it .001

 

[bang guy]

Originally Posted by mkroher
http:///forum/post/3172559
I'm willing to bet that if he does a 5gal water change with fresh water, he'll probably drop to 1.027.
I did hypo on a 29gal, and it took 3gal water changes of fw to lower it .001
At that rate it would take 45 gallons of fresh water on a 29 gallon tank to lower the specific gravity to 1.014.
I'm just sayin'

 

[the_bandit]

I actually did a 5g fresh water change and it went from 1.028 to 1.025
Ill start being a little more precise with measuring.
Thanks everyone.

 

[bang guy]

There's nothing wrong with 1.028. Why do you think that's wrong? It's probably a lot better than 1.025.

 

[aquaknight]

While different salts will yield different salinities per a 1/2 cup of salt, I don't think there's even been a brand that will give you 1.028sg using 1/2cup of salt per gallon.
If you're using a hydrometer, find someone locally with a refractometer, and see the differences in yours, vs. a refrac. Most LFS's should do this.

 

[bang guy]

Originally Posted by AquaKnight
http:///forum/post/3172592
While different salts will yield different salinities per a 1/2 cup of salt, I don't think there's even been a brand that will give you 1.028sg using 1/2cup of salt per gallon.
If you're using a hydrometer, find someone locally with a refractometer, and see the differences in yours, vs. a refrac. Most LFS's should do this.
Excellent point!

 

[flower]

Originally Posted by meowzer
http:///forum/post/3172540
Yeah...when I mix mine, I test the salinity....if it is too high...I just add a little more ro until it is where i want it
+1
This is what I do as well.

 

[flower]

Originally Posted by Bang Guy
http:///forum/post/3172589
There's nothing wrong with 1.028. Why do you think that's wrong? It's probably a lot better than 1.025.

My book says the ocean is 1.026 and SG should not be higher than that...I read here o the site all the time that above is okay...

..comment please.

 

[the_bandit]

Yesterday I went to two different LFS and they both read 1.028 using a refractometer. I dont like it that high because I wanted a Mantis and I guess my salinity was too high for it and it wound up dying. Just a personal preference to keep it lower.

 

[louti]

Originally Posted by Bang Guy
http:///forum/post/3172589
There's nothing wrong with 1.028. Why do you think that's wrong? It's probably a lot better than 1.025.
Yes, please clarify bang. I always thought 1.025-1.026 is ideal. I don't think 1.028 is an immediate problem, but shouldn't it be lowered?

 

[reefkprz]

I have been running my reefs at 1.027 for years. before I had ATO I often had evap push my SG up to 1.030 with no deletorious effects. its sudden increases that can cause osmotic problems in weak fish (the higher your Sg goes the more energy a fish requires to osmoregulate, hence a weak fish may succumb to something if it suddenly goes from 1.023 water to 1.028 water.) but I have never heard of or seen any conclusive evidence that a SG of 1.027-1.030 is fatal to anything, or even harmfull.
the only reason I can think of to run it lower than what I do would be to save on salt.......

 

[bang guy]

Originally Posted by louti
http:///forum/post/3172652
Yes, please clarify bang. I always thought 1.025-1.026 is ideal. I don't think 1.028 is an immediate problem, but shouldn't it be lowered?

In my opinion 34ppt (generally a S.G. of about 1.025 - 1.026) is the minimum, not the ideal.

 

[bang guy]

Here's a map of ocean salinity. Note the tropical areas where reefs are present generally range from a salinity of 34.5 up to 37ppt. At 80F that would be a S.G. range of 1.026 up to 1.028.