How Much Two Part Do I Need?

[redfishbluefish]

Sorry for the late response....for some reason I didn't get a notification that you had posted.

If you are going to bake the baking soda (sodium bicarbonate) to convert it to soda ash (sodium carbonate), you start with 594 grams of baking soda (which is approximately 2 1/4 US cups). Knowing US to UK cups is 1.2 to 1.0, respectively, you would need 1.87 UK cups of baking soda.

If you are starting with soda ash (sodium carbonate), that calls for 2 US cups. This translates to 1.67 UK cups. When I get home, I'll calculate the actual gram amount, but I suspect it will be around 525 grams. I'll get back to you on that.

As far as too much soda ash, you are approaching solubility, and what will happen is that it won't go into solution.

 

[redfishbluefish]

Wow, the assumption above was that density of bicarb was similar to carb.....NOT!

By calculation only to get equivalence of 594 g of sodium bicarbonate......it would require around 372 grams sodium carbonate.

Hope this helps.

Also, something else just hit me.....I think you guys use imperial gallons. The above recipe is for US gallons. Converting US gallons to Imperial gallons is 1.0 US gallon = 0.83 Imperial Gallons. So you would want 372 grams soda ash to 0.83 Imp. gallon of RO/DI water OR 448 grams soda ash to 1.0 Imp gallon.

 

[Sdiesel77]

Very helpful indeed Paul!!!
Thanks so much!
I'll make it a round value to be easier by using 600gr to bake and 380gr to be mixed to water
And next step, calculate the correct mix value per litre [emoji14]

 

[Randy Holmes-Farley Verified Community Expert]

Hi Paul,
One question if you know the answer, how many grams of Soda Ash is it when you say 2cups of it make 1 Gallons of Alkalinity solution?
What's happening if I put too much Soda Ash in the the RO water? It just stop dissolving?
Thanks

You cannot dissolve more than the solubility limit, but that limit is a bit above the normal recipe, so don't just add excess.

When the recipe calls for 594 grams (~2.25 cups) of baking soda before baking, that is equivalent to 375 grams of sodium carbonate.

 

[redfishbluefish]

Very helpful indeed Paul!!!
Thanks so much!
I'll make it a round value to be easier by using 600gr to bake and 380gr to be mixed to water
And next step, calculate the correct mix value per litre [emoji14]

Calculates out to 99 grams soda ash per liter of RO/DI.

 

[Bradley Crumpton]

Thank you.

 

[Anthonygee68]

Excellent article, thank you for sharing your knowledge

 

[Xclusive Reef]

What salt are you guys using? is there a difference between brands when keeping SPS ?

 

[waxhawreefer]

I used hw reefer salt, it was good but trying something new and made in the us!! Fritz pro salt!!

 

[Xclusive Reef]

I used hw reefer salt, it was good but trying something new and made in the us!! Fritz pro salt!!

Fritz is kinda on the expensive side

 

[azbigjohn]

Perfect time for this to pop back up on my feed...

I am measuring my calcium, magnesium and alkalinity levels this week to try and get my daily usage. Just got a BM doser , and want to get it going.

 

[waxhawreefer]

Fritz is kinda on the expensive side

No really considering that it will make 205!gallons! But u decide, u have to try one like it or move on!

 

[PeterG]

Thanks Paul for putting together this excellent article. I’m fairly new to reefing and just getting started on 2-part dosing.
Picked up the BRS kit and will be dosing manually on my 90 gal. Started a few days ago getting my numbers to BRS’s suggested starting pints: CA 425ppm; ALK 9.0dKH;
and Mag 1350ppm.

Today I start my daily dosing and if I’m reading the BRS instructions right (I’ve got a mix of LPS, Softies and a fe SPS) I should be adding .2ml per gal X 90 gal = 18ml of CA and ALK each day. Is this correct? I was pretty confident until I read that some members were dosing several hundred ml/day. Evan a 200 gal tank would only use 40ml based on the BRS formula.

I’m also using the Salifert test kits and find them easy to interpret.

Thanks again for putting all this info into together

 

[redfishbluefish]

Thanks Peter. First off, every tank is different. If you're just starting out with hard corals, low volumes of alk and calc would be expected. I'd suggest you start with what the BRS instructions state....as a starting point. Test again in a day or two and adjust volume as needed. Continue tracking and adjusting until you find the amounts that maintain your alk and calc where you want them. Initially you will be testing frequently, but as you dial in you levels, testing might be weekly, to every two weeks, to whatever time period you feel comfortable with minimal changes in alk and calc levels. I know my mature tank so well that I only test about once per month. But when starting out, I was testing very frequently....sometimes a couple times a day.

With testing you what to try and do this at about the same time of day.

 

[PeterG]

Thanks Paul. I appreciate the info & prompt reply

 

[Tautog]

FWIW, WC’s can meet all your needs for coral growth. I have a 200 gal system, 2 1/2 yrs old, 60-70 corals ( mixed ). I only started with 2- part, BRS, 10 months ago. My consumption has gone from 50 ml/ day/ 2- part to 200 ml/ day. I do WC’s every week or 2 weeks when my numbers fall from increased consumption of 2- part. The WC usually straightens things out, and the increase is calculated, corrected, and retested for a few days to make sure levels balance. Coral growth has been exceptional. Ive changed my feeding to less, but more times per day. I have also let the tank get dirty, only weekly suction of debris. Skimmer collection has gone from brown to dark green to black. Chase Alkalinity, match Calcuim, don’t worry about everything else, it will fall into place. High Nitrates aren’t all bad.

 

[Randy Holmes-Farley Verified Community Expert]

FWIW, WC’s can meet all your needs for coral growth.

Yes, but you need massive water changes daily to accomplish it if the demand is on the medium to high end.

Even a low demand of 0.56 dKH per day is not maintained by water changes unless you change more than 10% every day using a high alkalinity mix:

Water Changes in Reef Aquaria by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2005-10/rhf/index.php

Figure 23. Alkalinity as a function of time when performing very large daily water changes of 0% (no changes), 5%, 10%, 15% and 30% of the total volume EACH DAY. In this example, alkalinity is present at 4 meq/L (11 dKH) at the start and is depleted at a low rate of 0.2 meq/L per day.

 

[jsker]

First time seeing this, great informations

@Randy Holmes-Farley can you direct me to the thread were something was mentioned about add something to the alk part of the 2 part to boost PH?

 

[Randy Holmes-Farley Verified Community Expert]

First time seeing this, great informations

@Randy Holmes-Farley can you direct me to the thread were something was mentioned about add something to the alk part of the 2 part to boost PH?

It's a different formulation, using sodium hydroxide instead of sodium carbonate (or sodium bicarbonate), for about twice the pH boost per unit of alk and calcium added:

https://www.reef2reef.com/threads/new-diy-two-part-recipes-with-higher-ph-boost.344500/

 

[redfishbluefish]

@jsker , I believe you are talking about this recent post that not only raises pH, but now makes it truly a "two part."

New DIY Two Part Recipes with Higher pH Boost