Salitity

[reefguru21]

I was just pondering this question today is I has surfing some of the reef aquarium home sites on the web.

 

From what I read alot of veteran reef keepers run what I considers high range 1.026 and up.  I run around 1.019-1.021.  Is there any advantanges to running a higher salitity?  Does this effect coral and invert growth and health?  Just thought I'd ask to see if I'm missing something.

[Toyfreek]

Hi,

I keep my tanks around 1.024-1.025

My fish would rather have it around 1.021

My corals would rather have it 1.026

From what I have read and through my own expierience My corals are happier there.

Most of the LFS's including the one I work at Part time keep all thier tanks lower like in the 1.021-1.019 this saves on salt costs and is easier on the many more fish they sell rather than the minority corals.

HTH,

Toy

[Smokey Joe]

Salinity certainly matters.  In general corals are more sensitive than fish and research should be done to determine appropriate ranges for those that you're considering stocking.

 

I think though, you're confused about the difference between specific gravity and salinity.  Specific gravity is a density measure and will vay with temperature.  For this reason it's really meaningless (to a point) to talk about specific gravity readings without knowing the temperature they're measured at.  Salinity is a measure of the amount of salts dissolved, and therefore isn't dependent on other parameters (this also means don't trust the salinity measurments on hydrometers).  Typical salinity readings are around 35 or so.  My advice would be to tailor your salinity to recommended values by converting your sg reading at its respective temerature.  

[Toyfreek]

Hey Smokey,

What would the varience be between Say 78-80F?

or 82-84F?  

Given that these would be the low and higer end of most reef tanks a hydrometer would still be usefull if taken with temperature as well.

TIA,

Toy

[Jefe12234]

The difference in SG readings taken at 78 and 84 is about 0.001. It's not a huge difference, but it does have an effect. Smokey Joe is right. If you want to be accurate, pick a salinity (since this value is independent of temp). Then find corresponding temp and SG values.

 

reefguru, 1.019-1.021 is a very low SG. Many fish and some corals will tolerate those levels, but they are being stressed. Consider the fact that most reefs have a salinity of 35-38ppt. The middle value of 36.5ppt works out to a SG of 1.025-1.026 depending on temp. I would suggest slowly raising your salinity/SG for the health of your animals.

 

-Chris

[Sahin]

I agree, a SG reading of 1.025 at 80F will give a salinity of 35.8ppt, whereas the same SG at 75F will give a salinity of 34.8ppt approx.

 

So it does make a differance depending on the temp range.

Some poeple prefer to maintain thier tanks at a temp of about 74-75F while with other it is up to 80F, at those differences, one needs to be talking about salinity really.

 

Well, hope this is helpful is some way.

[Smokey Joe]

I didn't mean to say hydrometers are useless.  When the temperature is known they're fine, and since most of us have our tanks stable all were really interested in is relative shifts.  What is useless is the salinity readings on some hydrometers, because theres no way to know (short of calling the manufacturer) what temperature they were calibrated at.

[reefguru21]

I guess I should have put some more info on this.

well the Salitity is 28ppt

specific gravity is 1.021

tank temp  is at 78-80

My hydrometer is calibrated to 75 degrees

how much does this increase my actual salitity/SG?

Thanks for the responses they have helped clear up some confusion I was having.  I think I'll probably keep everything the same. My LFS runs at 1.023-1.027 and they've got thriving nanos and large systems.  

Thanks Smokey Joe =)

[Toyfreek]

If the flucuation is only 0.001 for a 6 degree difference thats really not much to consider. My evap gives me that kind of flucuation daily. thanks for clearing that up for me though.

Toy

[krusty]

everty place or person ive talked to has reccomended 1.023-1.025