Mixed reef salinity
 

just wondering what you keep your salinity at... im slowly trying to raise mine to around 1.025-1.026 but i was told by someone that "THATS STUPID"

Well, since a reef sits around 1.026 at reef temps, I'd think maybe it's a stupid person telling you that :) Only reason I can see to keep it lower is to save a couple of bucks a year in salt. If someone can't afford the proper amount of salt, maybe they picked the wrong hobby...

thats what i thought... i thought a reef was 1.026 but when i went in to marine aquaria they said its kind of stupid i should just keep it around 1.023-1.024 because my fish wont like it...

Ya, fish don't like it, they're jumping out of the ocean all the time to escape. sigh.....:)

I keep mine at 1.026 as well.

That's to funny to leave alone, I totally agree that whoever said that is stupid.:twised:

Reality is, based on the results here so far, that some people do not use enough salt. I'm curious as to the reasoning used to come to that decision. Did someone tell them it's stoopid and fish don't like salt? Trying to save a couple of bucks? Read it somewhere and think it's good advice?

We spend so much time dosing and measuring and tweaking to make sure everything is just right, but then don't add the right amount of salt....weird..

i also agree i have mine at 1.026...now.... i was using stupid hydrometer instead of a refractomer and to m surprise my salinity was at 1.036 for an undetermined amount of time.. i think my fishfeared i was making fish and chips but seemed healthy enough. but wheni dropped the salinity i had a bit of a hiccup and lost a few fish regertfully. now i watch more closely

I run mine at 1.025.

Mines at 1.025, Because its a thick line on my refractometer. I'm too blind to see the smaller lines.

It's just above the thick line.:mrgreen:

salinity
 

i run mine at 1.025 and no troubles yet, my only problem is trimming all the time!

1.025 - 1.026 is were mines at as well.

1.24-1.25 is where I keep mine.

maybe its be cause us newbies dont buy books we just talk to the LFS and they always suggest using a hydrometer and that has indication marks of 1.020-1.024 thats what i was told when i first started

Bahahahahahaha!!! Point made! Good one Brad. :mrgreen:

Natural Seawater average is 1.0264

Also the higher your salinity the better your skimmer works.

Could it be the confusion with hydrometers that were not calibrated to the proper temperature?

Martin Moe in the Marine Aquarium Handbook says that a hydrometer calibrated to 59 degrees will give a reading of 1.022 at 80 degrees, when the true reading should be 1.026.
John Tullock in Natural Reef Aquariums says in a chart one part of his book that the recommended level is 1.022-1.024 (page 119). In another part he explains a bit further, saying that "A typical glass hydrometer reading should be 1.022-1.024 at 75 degrees F" (page 67) but then tries to explain how temperature affects reading. He also says that seawater is 35ppt which "corresponds to an observed hydrometer reading of 1.024 at a tempurature of 75 degrees" (page 121) - No mention of whether or not that hydrometer is calibrated to 59 degrees or 75 degrees.

Confusing.

Anyway, tullock also says "Marine Aquariums are often maintained at a lower specific gravity in the belief that the lowered salinity reduces stress on fishes and makes the survival of parasites less likely. I am aware of no evidence to support this practice" (page 121)

I seem to recall the reason being that the lower salinity made it easier on the fish because they didn't have to work as hard to offset the loss of water from their bodies because of osmosis.

I keep mine at 1.024 at a water temerature of 78, read with a hydrometer calibrated to 75 - whatever that means.

I also keep mine at 1.024... I was a big believer of 1.025-1.026, and for almost 3 years of having my big tank, 1.026 is what I kept it at. But with the troubles I have had with SPS during the summer, and with some research, I have found that in nature many corals/fish are in the 1.023 - 1.025 range (liveaquaria.com also shows these ranges). So I decided to go in the middle at 1.024, and have had it at this reading for about a month or so now. Things seem just fine for coral and fish. So i am thinking the higher salinity isn't necessary.

I don't care about salt cost, and I am not on a budget... so price isn't an issue, I just want a healthy environment.

For those that can give reason why the higher salinity is better, please let me know why. I am more than happy to change it up again, but without just cause, I just don't see why I should anymore.

I keep mine at 1.026, simply because an undiluted reef is that value. I don't have any reason to say 1.024 is bad, other than it lowers other values (Ca, alk the big ones) at which point we then artificially raise the levels. I find it hard to believe it's stressful on the fish, as that is what their normal environment is (for reef fish). Local sea water is much lower, but I don't keep local species.
SPS thrive in the wild, at 1.026, and that value matches other things we don't measure (trace elements). Lowering salt lowers other values that may (or may not) be important, so without knowing for sure, I'll err on the side of where the livestock came from. I think, if anything, an unnaturally low level might introduce stress.

.024 for me as well

Salanity
 

The best way to keep track of the salt levels is using ppt (35) not specific gravity (1.024 ect). It is due to how salanity changes due to water temp -where as salanity (ppt) does not. I could try to go into the details myself but I just copied and pasted a very good explanation for you. Thank you broomer5 (saltwaterfish.com):biggrin:


The whole salinity vs specific gravity issue is not too tough to figure out. It all depends on the instruments used to do the measurements, what temperature they are calibrated for and which engineering unit you prefer to go by.

Salinity is expressed in parts per thousand ( ppt ).
It's just a measurement of the weight of the salt/minerals compared to the weight of the pure water.
Normal seawater is typically 35 ppt in most areas of a reef.

It could be 35 grams of salt per 1000 grams of water.
It could be 35 pounds of salt per 1000 pounds of water.
It could be 35 tons of salt per 1000 tons of water.

You could even use your own body weight as an engineering unit.
I weigh about 175 pounds.
I could easily say that the salinity of seawater is 35 broomer5's of salt per thousand boomer5's of water.
The weight ratio of salt (solids ) to water ( liquid ) is 35 TO 1000

Using ppt as the units then - the salinity would be considered to be 35 ppt at ANY temperature.

SPECIFIC GRAVITY on the other hand is not a weight to weight comparison. It is a weight to volume comparison.
When we talk weight to volume ~ we are talking DENSITY.
Density is just how much something weighs compared to how much space it takes up.

Picture a little clear acrylic cubic box that measures 1cm x 1cm x 1cm on the inside.
Fill it with pure water.
It now contains 1 cc ( cubic centimeter ) of water.
This little clear box of water contains exactly 1 milliliter of water.
1 cc = 1 ml

Now if you could weigh just the water in this little box ~ How much would the water alone weigh ?

The answer is IT DEPENDS.

The actual weight of this volume of pure water will depend on the temperature and the atmospheric pressure.

The metric standard for weight is grams.
It just so happens that this little clear box of water we have, if it's temperature was 4 degrees C ( 39.2 F ) and it was at sea level where the atmospheric pressure is 1 atmosphere ( 14.7 psi ) then the 1 cc of water ( 1 ml ) would weigh in at a whopping 1 gram.

In other words ~ 1 cc of water is 1 ml of water and weighs 1 gram. Were talking PURE WATER here.

This is how people came up with the term "Specific Gravity"
The DENSITY of water ~ how much it weighs ~ for a given VOLUME is referred to as the SPECIFIC GRAVITY.

In our pure water example above - the specific gravity would be 1.000

1.000 gram of pure water in a 1.000 cubic centimeter container.

Now the tricky part.

Water ( in a LIQUID state ) expands and contracts with temperature changes.
The warmer it is - it expands.
The cooler it is - it contracts.
When water expands or contracts - it either takes up more volume or less volume. But the amount of salt in the sample does not change. Only the volume of the water changes.
The ppt stays the same.

So ......... if we're using specific gravity as our measurement - we need to always look at the temperature of the saltwater too.
Specific gravity is a measurement of the WEIGHT of salt to the VOLUME.
Specific gravity is a measurement of the saltwater's DENSITY as compared to DENSITY of pure water - for the same volume of each.

There are a ton of charts on the internet, and in most any decent marine aquarium book. I can send you a chart if you want a good one. Be careful though - there are some contradicting charts floating around out there.

We'll use 3 different temperatures as examples, and the chart goes something like this.

At 60 degrees F
35 ppt = 1.026 S.G.

At 70 degrees F
35 ppt = 1.025 S.G.

At 80 degrees F
35 ppt = 1.023 S.G.

As you can see - the salinity is the same for each example.
It's still 35 ppt

But as the temperature goes up - the specific gravity goes down.

This is simply because the water expands at a higher temperature - and the density must therefore change as well.

Back to our little clear acrylic box of saltwater now.
The box is full of saltwater with a salinity of 35 ppt.

At 60 degrees F - the saltwater in this little box now weighs 1.026 grams.

At 70 degrees F - the box of same saltwater weighs 1.025 grams.

At 80 degrees F - the box of same saltwater weighs 1.023 grams.

The temperature of the saltwater MUST BE considered when using specific gravity as the measurement.

Okay you say - How does all of this crap mean anything to me and my marine tanks ???

You need to see what TEMPERATURE your hydrometer is CALIBRATED for.

Most refractometers or hydrometers are calibrated for liquids at a given temperature. The swing arm units like FasTests - I don't know what they are calibrated for. I don't like using them for that reason - plus they don't seem to give me good results.
They're okay if that's all you have, I still have one too.

The refractometer I use is calibrated for 68 degrees F.

The floating glass hyrdometer is calibrated for 75 degrees F.

What you need to do then - is measure the mixed up aerated saltwater with your instrument and thermometer, and write both values down on paper.
Then refer to a specific gravity vs. temperature chart - find your temperture you just wrote down and see what the S.G. is for that given temperature.
From a good chart for the marine hobby - you will also be able to determine the PPT salinity as well.

I like to mix my IO and RO/DI water to a salinity of 35 ppt.

The actual specific gravity of that batch of saltwater may be differerent - depending on the actual temperature I read on my thermometer, the instrument I use for S.G./Density and the chart I'm looking at to do the conversion.

Normally - I heat the RO/DI water with a heater - get it up around 78 -80 F ( my tank temperature ) mix in IO saltmix at 1/2 cup per gallon freshwater - toss in a little more salt and let it run overnight.

Then the following day - when I plan to do the water change.
Get out my tools - take the two measurements, thermometer and refractometer - look at the chart and tweek it up or down with a little more salt or a little more fresh RO/DI.

After doing this several times - I get lazy too - repeat the same procedures as I have before, get it as close as I can - and move on from there.

It doesn't have to be exact. It does need to be very close though.

The reasons why density, ppt and specific gravity are what they are IS very exact in every respect ......... but for my tanks - getting it real close is fine for me.

If you made it this far reading - congratulations - you must be interested.
If you have anything to add to this thread - please do so.
We're always interested in trying to figure all this stuff out - and any other views would be appreciated ;)

Plus - if it looks like my chart is not correct - please let me know.
As I said - there are several different charts out there - and I may have the wrong one too :eek:

I try to keep it at 1.025.

at the design referance temp (60 degrees F)
34.5ppt is actualy 1.026 not 1.024.
1.024 would be 31.9.

but this is confused more because people don't list the referance temp they are using for therte tables so you don't know. then I found two tables that said 80 degrees but were the values for 70 degrees :twised:

the problem is that you are not measuring salinity you are measuring the SG then coralaiting it to lines some one wrote beside the SG ones which will only corasponde at 60 degrees.



well you could buy and ATC one for 10 or 15 bucks more :mrgreen: but you will have to use the SG scale as the salinity scale will be wrong.

Steve

I keep mine at 1.024. I like it here as a little evaporation only raises it a couple points.... about 1.026.

Did you ask why they thought so?

lol....


1.025@80F

I guess i've always had it a tad high at 1.027, but i never thought that the fish would stress as much as the coral would.

they said i was because its to stress full for the fish... isnt a normal reef 1.026?? lol

I keep mine at 1.026. I have had no problems or issues.
This is a silly question tho. If my SG is 1.026, wouldn't the other elements and minerals in my saltwater be a little higher(like calcium and magnesium)than say if I used a 1.024 SG?:wink: That is why I use a little higher on the SG scale. JMO. But if I were running a larger system then say a 40-50g+ I think I would probably run my system a tad lower on the scale as with larger tanks you dose more so it would seem more realistic to run your SW at 1.024 SG(not due to cost either). In a smaller system, your WC water pretty much takes care of your calcium/mag/ replenishing of minerals.
Hard to say in all honesty. 1.024-1.026 seems to be the general rule for sure tho.

Hmmm, what is the benefits of running salinity at 1.026? The fish stores tell me to run at 1.024.

:lol: :lol: :lol: good one....

I run min at 1.026 as well.

1.025 for me. I mix my change water to 1.026 though to account for salt removed via skimming and creep etc.

Dude.... if your changing your water weekly or even every 2 weeks the change in salinity due to skimming & creep is not an issue. I can't believe this thread is still active. Like said before @ 1.026 the fish hate it so much they're jumping out of the ocean. bla bla bla temperature bla bla bla stuff bla bla bla more stuff. Let it go. The person at the lfs in the first post is a tool.:twised:

Again depending on the frequency of your water changes are,.... if your mixing your water changes to 1.026 depending on the volume of your changes, you may need to recalibrate your refractometer just to make sure your new water is @ 1.026 & not getting higher. Because after enough new water @ 1.026 goes into your tank your DT will be at 1.026 Whether you think so or not:twised:

Dude chill out. This is just a poll why are you so concerned about my 1.025 lol? I skim pretty wet and very slowly my salinity has crept down in the past. Ocassionally I'll also give people frags and some of my water so the trend is always very slow (but downward). To maintain 1.025 my small 10g changes (110g system) are mixed to 1.026. What's your issue and what does my post have to do with the LFS the OP mentioned? :biggrin:

My issue is that this is a boring topic, I can't believe that people are still debating about it & keeping this thread near the top of discussed topics. Also I can't believe that "skimming, creep, & giving some water away with frags" are actually factor's of your falling salinity. Nothing personnal but to me that's neurotic. :idea:

Just go & seek out info on any other big forum site & see what 99% out the TOTM keep theirs @.

Maybe I'm more generous with water when I give frags away =) Yeah it's a boring topic but my my salinity is constant what else can I say?