New DIY Two Part Recipes with Higher pH Boost

[Formulator]

@Randy Holmes-Farley, have you worked out the expected pH boost per ppm addition of the NaOH solution? I suppose I could do the henderson hasselbalch work myself but hoping you can save me the effort

 

[pav306]

Is there any reason this recipe would not mix correctly, I added 101.7g per litre of calcium chloride anhydrous, let it mix for a while then added 69g per litre magnesium chloride hexahydrate and let it mix in moth a pump. I then added 1.3g per litre of strontium chloride. The next day I bottled it and filled my dose container and it seems to have not dissolved fully and settled on the bottom, what did I do wrong?

 

[Formulator]

Is there any reason this recipe would not mix correctly, I added 101.7g per litre of calcium chloride anhydrous, let it mix for a while then added 69g per litre magnesium chloride hexahydrate and let it mix in moth a pump. I then added 1.3g per litre of strontium chloride. The next day I bottled it and filled my dose container and it seems to have not dissolved fully and settled on the bottom, what did I do wrong?

Your math works out for your choices of hydration forms of the salts… maybe order of addition could help, but there could also be impurities involved in precipitation depending on the salt sources. Try adding the magnesium first, followed by calcium and then strontium last. You might also be able to dissolve the rest in your existing solution with a little heat and longer mixing.

 

[Randy Holmes-Farley]

@Randy Holmes-Farley, have you worked out the expected pH boost per ppm addition of the NaOH solution? I suppose I could do the henderson hasselbalch work myself but hoping you can save me the effort

I have measured it but it is not a fixed number. It is higher at lower pH and higher at lower alkalinity.

At about 7 dKH and pH 8.1, adding 1.4 dKH instantly boosts pH by about 0.65 pH units, and it falls back from there as the tank pulls in CO2. If you spread that addition out, each boost is proportionally smaller, and the pH drops back after each one.

 

[Randy Holmes-Farley]

Is there any reason this recipe would not mix correctly, I added 101.7g per litre of calcium chloride anhydrous, let it mix for a while then added 69g per litre magnesium chloride hexahydrate and let it mix in moth a pump. I then added 1.3g per litre of strontium chloride. The next day I bottled it and filled my dose container and it seems to have not dissolved fully and settled on the bottom, what did I do wrong?

Combining calcium and magnesium chlorides often results in some calcium sulfate precipitation, with the sulfate coming as an impurity in the magnesium chloride.

 

[Randy Holmes-Farley]

No I don't. I will have to figure that out. Thanks!

Are you dosing anything for alkalinity now?

 

[pav306]

Combining calcium and magnesium chlorides often results in some calcium sulfate precipitation, with the sulfate coming as an impurity in the magnesium chloride.

Thanks Randy,

Should there be that qty though, do I need to heat and remix, adjust ph to try and dissolve it or do a controlled test to see if the solution gives expected cal rise?

When I stir it it turns to a cloady solution, as movement reduces it slowly coalesces forming fluffy cloady like lumps that then slowly sink to the bottom until it's settled out again.

 

[pav306]

I checked ph and it was 8.9, added a ml or 2 of 4.0n hydrochloric acid dropped to 7 and seems to have stabilised, I may have added the chemicals too quickly