17 replies to this topic

[washa]

Hi, can someone let me know where to buy Epson Salts. I have looked in the supermarket but couldn't find any.

[Fox]

Try Bunnings, Im sure they would have in bulk supply..

[the_german]

i saw it in coles

[keleherr]

got it IGA its in a blue box next to all the panadole n stuff

[Damosss]

got it at city farmers willetton. up to 20kg

[sajica]

Big W Gardening Section

[Leevers]

if your after salts to condition your water for cichlids, then try rift lake salt. works better IMO

Cheers
Chris

[EL]

pool salt cost close to nothing.

[OrangeBemba]

got it at city farmers willetton. up to 20kg

I get mine from the local heath food shop.

Just wondering, what does city farmers stock it for. Is it sometime for birds, dogs etc.. :-) Just wondering out of interested.

[Mr_docfish]

It is used in fertilizers as a source of Magnesium and sulphur.

Keep in mind it is hygroscopic (absorbs atmospheric moisture) so it will go hard if kept in open containers. Keeping products like these (such as riftlake salts) in very thick plastic bags will help in breaking it up and keep the moisture out. I can still remember in the past attacking a bucket of riftlake salts with a screw driver.... :x

doc

[Mr_docfish]

pool salt cost close to nothing.

It wont change the water chemistry in the form of pH or hardness though it is better than using nothing.

if your after salts to condition your water for cichlids, then try rift lake salt. works better IMO

Very true, it should contain about 20% or there-abouts of Epsom salts (magnesium sulphate) among other things like sodium carbonate and pottasium chloride.....but should not contain any extra sodium chloride (pool/rock/table salt) the lakes do not contain any of this. Riftlake salts are a better combination of all the available salts in the lakes.

Epsom salts may even be used as part of aquarium plant fertilizers.

doc

[anno1685]

Hi, can someone let me know where to buy Epson Salts. I have looked in the supermarket but couldn't find any.

Don't go looking under the salt section, go to the health food department where the vitamins and things are kept. Been getting mine from Woolworths, Coles and such.

[sydad]

Epsom salts is hydrated Magnesium sulphate made by recrystallising Magnesium sulphate from aqueous solution under carefully controlled conditions. It exists as the septahydrate with the formula:
MgSO4.7H2O (MW=246.47) and contains approx 10% by weight of Magnesium.

Far from being hygroscopic as doc says, it is in fact efflorescent: which means that in dry air it actually loses water of crystallisation, which may lead to the crystals becoming coated with a fine white powder. Depending on ambient temperature and humidity, in inadequate storage this can lead to as much as 50% of the water being lost; resulting in the proportion of Magnesium rising to about 13%.
Epsom salts does not absorb any more water even when exposed to air that is saturated with moisture. Caking or cementing may occur even in closed containers due to micro water movement between contacting crystals as temperature changes cause relative humidity changes within the container.

If Epsom salts is heated to 150+degrees C, the water of crystallisation drops by about 86% to give the monohydrate: MgSO4.H2O which contains approx. 16% by weight of Magnesium.
This "dried" form, which is not to be described as "Epson salts" is hygroscopic and will absorb atmospheric moisture to varying extent making the Magnesium content difficult to ascertain.(Heating to higher temperatures than 180 C results in the formation of basic sulphates of even more vaying formulae).

So what, you may ask. If formulating solutions of a reasonable required accuracy, it is necessary to know the degree of hydration of a salt such as Epsom salts. Most suppliers will provide this information, and pack chemicals appropriately. It is important to ensure that any chemical is kept in sealed containers, preferably in a cool, dark place. Refrigeration may be necessary, and if this is the case ensure that the container is allowed to reach room temperature before being opened to avoid condensation onto contents on opening.

Syd.

[Leevers]

all that information? i dont quite understand what your trying to say? no salt will reach a temp of 150 degree's in a tank

[sydad]

Hi Leevers,

Guess I became so carried away with technical details that I omitted to make my point clear: mea culpa. :oops: So I'll try now.

Unless you KNOW how to use chemicals, including calculating quantities from supplied data that may not have made clear precisely the fine details of ingredients, you may cause yourself considerable grief.

As an example, a friend showed me several samples of magnesium sulphate he obtained from different sources.
One was apparently correctly labelled as Epsom salts. It came from a reputable source, and was purchased in a local supermarket, but did not carry the formula on the label. Nevertheless it was reasonably well packaged, and the contents were clean, freeflowing crystals.

Another sample was labelled as Epsom salts (dried), and gave a formula of: MgSO4.3H2O. As I said in my previous post, this substance is NOT Epsom salts, but is partially dried Magnesium sulphate. However, assuming that the label was otherwise correct, it contained enough information to enable a user to calculate reasonably well the proportion of Magnesium present. The real problem was that it was purchased in a paper bag that had obviously been exposed to moisture, and which contained a caked mass which probably was not the labelled contents since dried Magnesium suphate, unlike Epsom salts CAN absorb moisture.

The final sample was presented in a thick plastic bag contained within a substantial carboard box which carried a label indicating that the content was: MgSO4.H20 (Technical) dried at 160 degrees C: and contained a free flowing white powder. Of the three samples this was by far the cheapest, and since my friend wished to mix a large quantity of a particular formula, I suggested that he use this sample. As he was not savvy with regard to chemicals, I showed him how to calculate the correct amount as the formula he was using specified Epsom salts, and that the final concentration of Magnesium was considered to be if not critical, then at least important.

The point is that the Magnesium content of the three samples varied by 60%. with one of unknown concentration (the second), and the first, which was useable, was also the most expensive by a considerable margin, especially when considering that the majority of the sample was water.

Sorry if I've rambled on somewhat, but I hope that I have made clear that some knowledge of chemistry, and the appropriate storage of chemicals is necessary if aquarists wish to safely make their own preparations from formulae that seldom list possible pitfalls.

Regards, Syd.

[coley]

wow thats a lot of info . but how much do you use and exactly what will it do to your tank water

[Leevers]

usually a tablespoon per 20L so they say. it creates a breakish water of which helps keep alot of tap water impurities stable. It also helps keep alot of the freshwater algae and fungus to a minimum. In my experience its certainly what i have noticed anyway

Cheers
Chris

[Mr_docfish]

Far from being hygroscopic as doc says, it is in fact efflorescent: which means that in dry air it actually loses water of crystallisation....Caking or cementing may occur even in closed containers due to micro water movement between contacting crystals as temperature changes cause relative humidity changes within the container.

Sorry Syd, my bad 8O , but the following info might explain my recollection from chemistry 201, which is fuzzy at times due to the bourbon....

....This "dried" form, which is not to be described as "Epson salts" is hygroscopic and will absorb atmospheric moisture to varying extent ....

I must remember to to bounce this detail by you first, this is the second time you have seen my weekness :oops: , i was never a gun at chemistry to be honest.

Thanks Syd, see ya round,
Oliver