Salts

Mekaeel

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howzit crew?
ive been wondering,how do you determine which is a good salt and which is bad/not all that good?ok.most of the packing of the various brands,state the the salt is nitrate free and phosphate free.ive been using the real ocean salt from andrew and found it to work for me and it is well priced.other brands solve the same pupose but are highly priced eg.tropic marine pro reef crystal which sells at +-R1000.00 for a 20kg if im not mistaken.can anyone elborate on this.
cool
 
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Tough one...

The best we can do as aquarists is test the basic parameters (i.e. SG, pH, Calcium, Magnesium, alkalinity) and also just observe visually what the salt looks like.

You want the solution to be clear when finished mixing, not cloudy. No undissolved material

Testing more than this is not really practical.

The distinguishing feature IMO of whether or not a synthetic salt is good or not lies in the minor/trace element composition/content and this is something which we cannot measure easily.

I've used a few different salts over the past 2 or so years (Kent, TM Pro Reef, Instant Marine, Real Ocean) and I can honestly not say one was better than the other.

So now I buy purely on price.

Clinton
 
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Can be a few reasons for this like precipitated calcium carbonate or similar, but could also be precipitated trace elements, or insoluble impurities, or perhaps other things like high pH, reaction with the make-up water (if not using RO) etc.

Can also be caused by how one makes up the salt water. If you add the water to a pre-weighed amount of salt it is possible to get this effect due to localised high concentrations of salts. Rather add the salt to the pre-determined amount of water while mixing.

Not too serious IMO (depends how turbid it is) but I just think we can really measure so little of importance, that I would rather just use the one that mixes up clear. That way you know that everything that was meant to be in solution is there.
 
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A faint cloudiness when all the salt has been properly dissolved could also be due to anti-caking/free flow additives that are used in sodium chloride to prevent it forming rocks (Cerebos - See how it runs).

I would not expect that a salt manufacturer would make a "mistake" like this but one never knows. The stuff is usually only fumed silica so not toxic or anything but still...
 
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I've used a few different salts over the past 2 or so years (Kent, TM Pro Reef, Instant Marine, Real Ocean) and I can honestly not say one was better than the other.

So now I buy purely on price.
Good point, but don't just look at the price per kg of dry salt - many (none?) of the brands don't mix to the recommended NSW (Natural Sea Water...) salinity if mixed at the manufacturer's recommended dosage. So, look at the price per liter of salt water, mixed to the NSW salinity of 35ppt (SG ~1.025 at 26 deg. C) to compare price.

A good indication of a salt's "goodness" (IMHO) is to do some research to establish how many "Tank of the Month" winners on forums such as Reef Central use a particular salt.

Hennie
 

Mekaeel

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A good indication of a salt's "goodness" (IMHO) is to do some research to establish how many "Tank of the Month" winners on forums such as Reef Central use a particular salt.

Hennie
that is an excellent idea hennie.i guess not only on reef central but also other thriving tanks.
 
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I never follow manufacturers guidelines as some of them are so obviously incorrect (eg 1 kg salt makes 40 litres, yes true but at what SG). But considering that all salts are essentially similar with respect to the major elements 99% of the salt) then just using a standard mass each time whatever the salt used should get you very consistent results.

NSW is generally 35 parts per thousand salts which is 35g salt per litre (35g salt made up to a volume of 1 litre). This will give a SG (25°C) of 1.023.

If you usually run higher than this dissolve a bit more per litre, lower then use a bit less. (32gl = ±1.021, 38g/l = ±1.025)

Clinton
 
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Yup, that's close - I mix 8.00 Kg of Tropic Marine Pro in 200 liters of water for an SG of 1.025 at 26 °C

As for preferred salt brand, even though one cannot test for *most* elements, one CAN check the calcium and alkalinity levels of the water, and I would opt for one of the better known brands giving high levels of calcium and alkalinity (that's why I prefer TM Pro Reef). I've used IO for quite some years before changing to TM, and have been very happy with it, apart from the LOW calcium level. I'm quite wary of local produced salts - I actually had a sample of a local brand analysed by our university, and the copper level (amongst others...) was WAY higher than IO or TM. I also managed to obtain unpublished data from their own analyses (done by the CSIR) which were just as bad as my results. When I queried this with the wholesalers and the manufacturers, their reactions were not very confidance inspiring, to say the least...

Obviously, if I lived close enough to the ocean I would only use REAL sea water, containing REAL plankton and other "goodies" - that's all I used for about 5 years whilst living in Riversdale (on the Cape south coast), and I honestly believe that my tank was at it's best during this time. Of course, lugging ~200 Kg of water up a steep beach every week or two did wonders for my figure as well :)

Hennie
 
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...would you say that NSW has for eg. more calcium rather than synthetic?
No, I've found NSW to measure at about 380 ppm Ca. I do believe that the advantages of real, "live" NSW far outweighs the slightly low calcium content. I would gladly supplement a bit of calcium and use NSW, if I could.

Hennie
 

Galibore

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I must say that since my LFS sells salt water I haven't mixed my own. Been a while now. They use TMPR and always has the SG spot on, measured with refractometer. And best of all, it only works out slightly more expensive than mixing my own, which is a pain in the ass.
 

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I would have to go check again because I forgot. WIll check tonight and post here.
 

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