Homemade Two-Part Calcium and Alkalinity Additive System Questions

[Joe_Blog]

For the past three weeks or so, I have been using the Homemade Two-Part Calcium and Alkalinity Additive System (Recipe #1) with a dosing pump on a timer. It has been great in automating the system somewhat, maintaining stable parameters, and definitely economical. I make up enough for a 10L batch at a time. My question is regarding the baking soda mix. I am having quite a bit of crystallizing of the liquid. So much so that it completely clogged the dosing line solid and the whole inside of the plastic container was thickly lined with the solid crystals. When mixing the cooked baking soda, I use a very large pot on the stove to heat the water in order to aid in the dilution process. When I pour it into the dosing container, it is still quite hot, but definitely diluted. I checked the solution the next day and the crystallization was already significantly underway. Is this normal? Am I doing something wrong? Is there some way that I can avoid this?

I also wanted to ask about the magnesium DIY additive portion. In the recipe, it calls for Epsom salts. I was reading this article in http://ozreef.org/diy/magnesium_additive.html that suggested that I use magnesium chloride if available. I have made the substitution. Do you see any problems with this? My LFS warned that I may have problems with maintaining a constant salinity level, but shouldn’t be a factor if I make regular water changes. I do 10% every week and haven’t had any negative effects so far.

I’ve noticed that towards the end of the 10L batch (within the last 2 liters or so), my Ca and ALK levels start to fall. Do these solutions lose some of their potency over time? Would it be best to make up smaller, more frequent batches?

Thanks in advance for your help!

Steve

[Randy Holmes-Farley]

In both recipes, the volume of the water used is based on the alkalinity part, which is not far from its solubility limit.

The baking process makes the baking soda more soluble, hence the need for less water in the baked version. However, if the baking is incomplete, then there may be solids that will not dissolve at the concentrations involved.

So if you get incomplete dissolution when cool, I'd suggest just scaling up the water volume in the alk part (or both parts to maintain equal addition volumes).

If there is just a little solid present, that may be an impurity in the baking soda that won't dissolve at room temperature, and I wouldn't worry much about it.

These solutions will maintain potency over time, so I don't know why the effects that you see decline over time.

I was reading this article in http://ozreef.org/diy/magnesium_additive.html that suggested that I use magnesium chloride if available. I have made the substitution. Do you see any problems with this?

I do not generally recommend Epsom salts as it raises sulfate relative to chloride. In this recipe, however, there is a ton of chloride coming from the calcium chloride, and that offsets the sulfate from the Epsom salts.

If you use magnesium chloride with this recipe, then you will actually deplete sulfate over time, both from the calcium chloride and the magnesium chloride additions. I haven't worked through the math, but equal parts of magnesium chloride and Epsom salts would be better than magnesium chloride alone. Do you have a source of magnesium chloride?

[pmui]

hi,

I a bit confused on the dosing amount.
I have a 55gal. tank and i've made reciept #2. How much do i dose everyday?

thanks,
Peter

[pmui]

hi,

I a bit confused on the dosing amount.
I have a 55gal. tank and i've made reciept #2. How much do i dose everyday?

thanks,
Peter

[Joe_Blog]

So if you get incomplete dissolution when cool, I'd suggest just scaling up the water volume in the alk part (or both parts to maintain equal addition volumes).

I did up the water quantity by half a liter and everthing is great. No more crystals and no more clogging of the lines/pump.

These solutions will maintain potency over time, so I don't know why the effects that you see decline over time.

I am guessing that this was due to the pump getting clogged with the crystals. I just made up all new batches, so will have to wait a couple weeks before they run out and can see what happens to my parameters.

I haven't worked through the math, but equal parts of magnesium chloride and Epsom salts would be better than magnesium chloride alone. Do you have a source of magnesium chloride?

I just followed your suggesting of equal parts. I'm still doing the 10% per week water changes, which should help keep things in check. I have a local chemical company that supplies both the magnesium chloride and calcium chloride. I can get a 25KG bag of both for less than $25NZ total (~$17US). :D

I wanted to thank you Randy for your help and economical recipe. My water parameters are finally stable with very little maintenance, and everything else here in New Zealand is so expensive that it is finally nice to have a deal on something. :)

[Randy Holmes-Farley]

I a bit confused on the dosing amount.
I have a 55gal. tank and i've made reciept #2. How much do i dose everyday?

I don't give dosing amounts in the article because it ought to be based to the actual demand of the aquarium. So it is best determined by trial and error. Start with a dose (say, 1 ml per 2-4 gallons of tank water) and then ramp up or down over time as the testing suggests. I'd focus on alkalinity as it responds a lot faster to over or under dosing.

[Randy Holmes-Farley]

I did up the water quantity by half a liter and everthing is great. No more crystals and no more clogging of the lines/pump.

That's great! :)


I am guessing that this was due to the pump getting clogged with the crystals. I just made up all new batches, so will have to wait a couple weeks before they run out and can see what happens to my parameters.


That could well be. Hopefully, it will no longer happen. :)

I wanted to thank you Randy for your help and economical recipe. My water parameters are finally stable with very little maintenance, and everything else here in New Zealand is so expensive that it is finally nice to have a deal on something.

You're welcome. Glad to be of service to the folks down under. :)

[pmui]

thanks Randy.

Peter

[Randy Holmes-Farley]

You're welcome.

Happy reefing. :)

[chem_fun]

I would like to also add a thank you. The DIY recipie is wonderful. Havn't had a problem since. Being that it was for a school, DOW graciously send someone to our school with two bags of DOW Flake. I now have enough to last a LONG time.

[Randy Holmes-Farley]

Being that it was for a school, DOW graciously send someone to our school with two bags of DOW Flake. I now have enough to last a LONG time.

Wow, that's great. You're welcome and good luck!

[Joe_Blog]

Hi Randy-

The DIY recipe is doing great holding my parameters just right! Thanks again!!

I just had a follow up question regarding calcium buildup on the interior of the plumbing and pumps. In the two months that I have been using the recipe, the buildup has been fairly extensive, i.e. about 2 millimeters in the pipes and the interior of pumps are pretty caked. Is this normal? I’ve never used a calcium reactor before. Do you get the same buildup with that type of system?

Cheers,

Steve

[Randy Holmes-Farley]

I don't use the two part (I use limewater).

That said, such buildup would come from excessive pH (or calcium or alkalinity) and low magnesium).

Are you using the baked recipe and what pH does your aquarium attain? Are you dosing near the inlets to those pipes?