I would be careful with Steam Iron Water as it may have perfume in it!
De-ionsed water for cars will be okay!
De-ionsed water for cars will be okay!
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KCl and KH2PO4 solubility
- Thread starter Fuzzy Shaq
- Start date
Aleman
Member
But avoid battery top up fluid, as that may not be just deionised water (even if labelled as such) ... Could contain sulphuric acid!
Hi all,
Rain-water will also do at a pinch, it is <"steam distilled"> before cloud formation and only picks up atmospheric pollutants. The problem with tap water is that it often comes from a limestone aquifer and is fully saturated with calcium (Ca++) and bicarbonate (2HCO3-) ions, and it is these ions that then form <"insoluble compounds"> like calcium phosphate complexes.
cheers Darrel
I didn't know that, I always just get a small amount from the <"lab. DI unit">. I don't know exactly how much DI water we get through in a week (for rinsing the glassware etc), but it will be hundreds of litres.
Distilled, <"DI or RO water is perfect">, it is the lack of ions that makes it suitable, it is just a blank slate to start off with. What we call "water" is really a weak solution of salts with H2O as the solvent. Because H2O is an <"amphoteric solvent"> a lot of substances will go into solution in it.
Rain-water will also do at a pinch, it is <"steam distilled"> before cloud formation and only picks up atmospheric pollutants. The problem with tap water is that it often comes from a limestone aquifer and is fully saturated with calcium (Ca++) and bicarbonate (2HCO3-) ions, and it is these ions that then form <"insoluble compounds"> like calcium phosphate complexes.
cheers Darrel
X3NiTH
Member
- Joined
- 13 Apr 2014
- Messages
- 1,647
My tank that’s been running for 3 years and only had 2 waterchanges with 0.15ppm of Mn dosed every week as part of micro addition, GH and KH are above 10 , TDS has climbed over the years from about 150ppm to over 500ppm, Mn is still only reading around 0.1ppm at any measured point (Using a Hannah Colorimeter). Unchelated Mn won’t accumulate and will drop out of solution quite quickly if you forget to dose regularly.
Tank looked like this at time of testing -
Fuzzy Shaq
Member
Hi all,
cheers Darrel
Unfortunately a bit of chemistry is inevitable. I'm not a chemist, I've found a lot of <"chemistry quite difficult to understand"> and I still only know the bits <"I've run into over time">.
cheers Darrel
Hi all,
When we make up stock solutions in the lab. we use a magnetic stirrer and hot plate, but you still can't exceed the total solubility limits.
cheers Darrel
Yes, solubility increases for most salts with temperature, <"carbonates are the exception">. The problem is that as the water cools they tend to come back out of solution, the <"least soluble salt first">. You can increase carbonate solubility by reducing the temperature <"and/or adding CO2">, but the same applies, as the temperature rises, or CO2 escapes, the carbonates come back out of solution.
When we make up stock solutions in the lab. we use a magnetic stirrer and hot plate, but you still can't exceed the total solubility limits.
cheers Darrel
So it's a false good idea, i don't use any carbonate i think, chloride and sulfates mostly, is the microwave change salt reaction, It seems to me that the microwave makes the water molecules rub together to heat up ? won't alter the salt ? thx
Hi all,
The issue would come with compounds like calcium sulphate (CaSO4.2H2O) which have low solubilities <"0.26 g/100ml at 25 °C (dihydrate)"> and where heating won't make much difference to that.
cheers Darrel
It is literally <"just the heating">, it doesn't matter how you heat the water.
All chlorides (other than <"silver chloride (AgCl)"> are soluble.
The issue would come with compounds like calcium sulphate (CaSO4.2H2O) which have low solubilities <"0.26 g/100ml at 25 °C (dihydrate)"> and where heating won't make much difference to that.
cheers Darrel
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Hi @Vsevolod Stakhov
I use the JBL potassium test kit. See below:
JBL PROAQUATEST K Potassium
For perfect aquarium plant growth: determines the ideal potassium value to monitor the fertilisation of freshwater tanks
www.jbl.de
I'm in the UK.
JPC
Hi all,
Potassium (K) is one of the easiest metals to test for with <"analytical kit">, either ion selective electrode or flame photometry AAS, ICP etc.
cheers Darrel
It gets a mention earlier in <"the thread">. It should work OK, other than the difficulty of saying exactly when the "X" has disappeared.
Potassium (K) is one of the easiest metals to test for with <"analytical kit">, either ion selective electrode or flame photometry AAS, ICP etc.
cheers Darrel
Thanks, i succeded the mix for K2SO4, KNO3,CaCl2, MgSo4,Urea, all in individual bottle of course for a more precise dosage, the only one that trouble me is KH2PO4, there is always few in the bottom. I've been surprise with K2SO4, crystal clear, once i shake it, you see all the potassium
It might be a dumb question but to be sure, my 500 ml K2SO4 + H2O i made is my storage backup bottle. I made that mix to deliver 2 ppm K every 1.6 ml. My little pump 100ml deliver 1.6 ml. So if i'm right as long as i don't add anaything, the ppm never change ? i mean if i take 100 ml from the storage bottle and put it to the pump bottle, the 1.6 ml will still deliver 2ppm K ? thx
It might be a dumb question but to be sure, my 500 ml K2SO4 + H2O i made is my storage backup bottle. I made that mix to deliver 2 ppm K every 1.6 ml. My little pump 100ml deliver 1.6 ml. So if i'm right as long as i don't add anaything, the ppm never change ? i mean if i take 100 ml from the storage bottle and put it to the pump bottle, the 1.6 ml will still deliver 2ppm K ? thx
MichaelJ
Member
Hi @eminor, Yes, if indeed the storage bottle delivers 2ppm per 1.6 ml to your tank and you transfer 100 ml from the storage bottle to a 100 ml pump bottle it will deliver the same 2 ppm. per 1.6 ml. pump... Do shake the storage bottle well before you transfer to the pump bottle.
Cheers,
Michael
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