DIY Boron Dosing Solution

[PSXerholic]

Hello Randy,

I do like to create a Stock solution of Boron , ideally in 1000ml portions, that should be around in the 5000ppm range.

Could you reveal to me how much I would need to mix a solution like this?

Thanks a lot and I'm a great fan of your DIY solutions ;-)

-Andre

 

[JimWelsh]

Sodium bromide (NaBr) contains no boron (B). Bromine (Br) and boron (B) are different elements.

 

[PSXerholic]

It's late !!! Let me correct that ;-)
THX Jim

 

[PSXerholic]

THX

 

[Randy Holmes-Farley Verified Community Expert]

5,000 ppm of borate or boron?

Sodium Borate Decahydrate has a molecular weight of 381.4 g/mole and boron is 10.8 g/mole, so it is 2.8% boron by weight.

To get 5000 ppm boron in a liter, add 5,000 mg/L / 0.028 = 177,000 mg/L.

This site says the solubility is only 38,000 ppm, so you may have to settle for a lower concentration stock solution:
https://www.scbt.com/scbt/product/sodium-tetraborate-decahydrate-1303-96-4

 

[PSXerholic]

5,000 ppm of borate or boron?

Sodium Borate Decahydrate has a molecular weight of 381.4 g/mole and boron is 10.8 g/mole, so it is 2.8% boron by weight.

To get 5000 ppm boron in a liter, add 5,000 mg/L / 0.028 = 177,000 mg/L.

This site says the solubility is only 38,000 ppm, so you may have to settle for a lower concentration stock solution:
https://www.scbt.com/scbt/product/sodium-tetraborate-decahydrate-1303-96-4

Thanks a lot Randy, as well for the detailed explanation of the formula.

The lower solubility makes sense now, since I tried before to dissolve 7,000mg in a 1 Liter Jar with not much success ;-)
I had to double the amount of water and still did see fiber/crystals in the solution.

No wonder that a product on the market that specifies ~5,600ppm min has always chunks of crystals and borate left after shaking the bottle ;Rage
Also it explains why other Boron solutions out there are so weak in it's mixture.

I will use the diluted version to get a nice clean solution, and will then dial in the tank slowly.

So here my late night math attempt:
1,000mg Borate/L/ 0.028 = ~35,400 mg/L Boron

So does the below makes sense?
1ml solution is 35.4ppm
1ml solution to 100L tank water = 0.354ppm increase
1ml solution to 1200L tank water = 0.0295 ppm increase
34ml solution to 1200L tank water = 1.003 ppm increase

-Andre

 

[Randy Holmes-Farley Verified Community Expert]

So here my late night math attempt:
1,000mg Borate/L/ 0.028 = ~35,400 mg/L Boron

So does the below makes sense?

Must have been very late at night.

1,000 mg/L (borate product added per liter) x 0.028 (fraction boron in the product) = 28 ppm boron in that solution.

 

[PSXerholic]

Must have been very late at night.

1,000 mg/L (borate product added per liter) x 0.028 (fraction boron in the product) = 28 ppm boron in that solution.

Randy, thx a lot for taking the time to support on this subject ;-)

 

[PSXerholic]

Indeed it was a long day and a short night before ;-)
Thx, this formula makes it easy to adapt also to other chemicals if moles are known.

So,
solution is 28ppm
1ml solution to 100L tank water = 0.00028ppm increase in a 100L volume
1ml solution to 1000L tank water = 0.000028 ppm increase in a 1000L volume

50ml per day on a 1200L tank would then be 0.00117ppm. That times 180days would compensate a theoretical consumption/precipitation of 0.21ppm Boron for a 1/2 year.

I may try 2,000mg then to make a 56ppm solution.
That means testing to see how much Boron the tank really takes up to maintain 8-9ppm as soon it appears stable. I expect about a drop of 0.5ppm per 6 months, from my experience on my previous Coral Forest.

Randy, thx a lot for taking the time to support on this subject ;-)

Btw. I read in your article about Boron a while ago that Boron sinks.
Does that also applies for Dosing stock solutions?
I was thinking to run the solution through a doser hourly.

 

[Randy Holmes-Farley Verified Community Expert]

Btw. I read in your article about Boron a while ago that Boron sinks.
Does that also applies for Dosing stock solutions?
I was thinking to run the solution through a doser hourly.

Sinks? As in dissolved boron sinking in the stock solution or in the tank? It shouldn't.

 

[PSXerholic]

Sinks? As in dissolved boron sinking in the stock solution or in the tank? It shouldn't.

Thx. I looked it up again since it was quite a while ago and the word sinks was meant in a different context.

 

[Randy Holmes-Farley Verified Community Expert]

Thx. I looked it up again since it was quite a while ago and the word sinks was meant in a different context.

OK, thanks.

 

[Stigigemla]

With the molecular weight of 381 i guess it would be 2 Sodium and 4 Boron in the molecule.
It would then contain 11,3% Boron.
I used 113 grams Borax ( di sodium tetra boron.... decahydrate) which i filled up with osmosis water to 1000 grams to make mine stock solution..
1ml of that solution will raise the boron 1mg/l in 100 liters of tank water.

 

[Randy Holmes-Farley Verified Community Expert]

Sorry, you are right, it has 4 borons and is 11.3% boron by weight.

 

[nanomania]

Wow.. thats still confusing for me.. so whats the final formula? Which boron salt to howmany liters of water?

 

[Randy Holmes-Farley Verified Community Expert]

Post #13 has the correct formula[emoji3]

 

[nanomania]

Post #13 has the correct formula[emoji3]

113 grams di sodium boron decahydrate which in 1liter of water? Howmuch to dose?

 

[Randy Holmes-Farley Verified Community Expert]

113 grams di sodium boron decahydrate which in 1liter of water? Howmuch to dose?

Post 13 says:
1ml of that solution will raise the boron 1mg/l in 100 liters of tank water.

 

[nanomania]

Post 13 says:
1ml of that solution will raise the boron 1mg/l in 100 liters of tank water.

Do we get boron testkits?

 

[Randy Holmes-Farley Verified Community Expert]

Do we get boron testkits?

There are boron kits, at least last time I tested some, but ICP also gives boron results and one test may not cost much more than a new kit. I also was not impressed with the accuracy of some that I tested, but that was a long time ago and the kits may have changed.