Mag dosing question

[virginiadiver69]

Until recently I've been relying on limewater only for my Calcium and Alk maintenance.
Now I'm relying on 2 part, using Dowflake and baked baking soda and seem to remember some talk about different ratios of Dow Magflake to Epsom salts depending on dosing habits.
I skimmed through Randy's articles but did not see anything.
Randy seems to be taking a well deserved break so if anyone else can clue me in I would appreciate it.

[HighlandReefer]

I misread your post. You mix MagFlake with Epsom Salts at a 10:1 ratio as a mag. supplement.

[virginiadiver69]

Does the reef calculator take the different mix into account or does it even matter?
Thanks for the reply.
Is this outlined in any of the articles?
At a 10:1 ratio...why even use Epsom salt at all?

[HighlandReefer]

The concern with using Magnesium Chloride only is that it will increase the chloride levels higher than found in NSW. The concern about Epsom salts only is it will increase your Sulfate over that found in NSW. By combining in the ratio noted above, it will provide an ionically balanced mix which will maintain your water parameters to that equal to NSW.

Randy's article on do-it-yourself mag. supplements states:

"To perfect such a recipe, it's imperative to know the amounts of sulfate in Epsom salts (39%), the amount of chloride in magnesium chloride hexahydrate (34.9%), and their bulk densities, because most aquarists will use a volume based measurement (1.05 g/cm3 for Epsom salts and 0.85 g/cm3 for magnesium chloride hexahydrate solids). Taking all these factors into account, the desired volume ratio is 10:1, MAG flake to Epsom salts, as a supplement; for instance, 10 cups MAG flake and 1 cup Epsom salts."

http://reefkeeping.com/issues/2006-07/rhf/index.php

[xJake]

Originally posted by virginiadiver69
Does the reef calculator take the different mix into account or does it even matter?

This one does: http://reef.diesyst.com/flashcalc/flashcalc.html

Choose "Randy's Recipes 1 and 2 versions A and B"

[virginiadiver69]

Okay...I see, thanks.
When would the 5:3 ratio be used?
Jake, that was the calculator I was referring to. How do you know which ratio it accounts for?
Thanks for the article link...I have not found that one yet.

[xJake]

It uses the 10:1 ratio. Dieck has done a great job of keeping the calculations updated to Randy's latest findings. If you look at the "update" list at the bottom of the calculator page then you'll see he updated it just after Randy's latest article discussing Mg was published.

[virginiadiver69]

Good to know...thank you.

[virginiadiver69]

Forgot to ask...can I use the same 10:1 mix to boost my IO mix?

[xJake]

Originally posted by virginiadiver69
Forgot to ask...can I use the same 10:1 mix to boost my IO mix?

Yep.

[virginiadiver69]

Okay...sorry to belabor this but, I just finished reading the linked article and a couple points stood out:

"3. Using both Epsom salts and MAG flake,dissolve 7¼ cups MAG flake and ¾ cup Epsom salts in one gallon of water, and use that to supplement magnesium in amounts determined using this linked online calculator, with the entry "Randy's Recipes 1 and 2 Versions A and B," and ignore for this purpose what those designations mean.This recipe is preferred, but its advantage over recipe #2 is minimal in most cases."

The 7 1/4c and 3/4c formula looks like something more like an 8:1 ratio. Am I splitting hairs here?

It looks like doing regular 1% daily or 30% monthly water changes negates any need for Epsom salts at all.


"Note also that this recipe (#3) is different from that given in my DIY two-part recipe, because in that case more magnesium sulfate is necessary to offset the rise in chloride that is provided by both the calcium chloride and the magnesium chloride."

This makes it sound like someone that uses Randy's DIY 2 part should use the original 5:3 ratio.

[xJake]

Originally posted by virginiadiver69
Okay...sorry to belabor this but, I just finished reading the linked article and a couple points stood out:

"3. Using both Epsom salts and MAG flake,dissolve 7¼ cups MAG flake and ¾ cup Epsom salts in one gallon of water, and use that to supplement magnesium in amounts determined using this linked online calculator, with the entry "Randy's Recipes 1 and 2 Versions A and B," and ignore for this purpose what those designations mean.This recipe is preferred, but its advantage over recipe #2 is minimal in most cases."

The 7 1/4c and 3/4c formula looks like something more like an 8:1 ratio. Am I splitting hairs here?

It looks like doing regular 1% daily or 30% monthly water changes negates any need for Epsom salts at all.


"Note also that this recipe (#3) is different from that given in my DIY two-part recipe, because in that case more magnesium sulfate is necessary to offset the rise in chloride that is provided by both the calcium chloride and the magnesium chloride."

This makes it sound like someone that uses Randy's DIY 2 part should use the original 5:3 ratio.

You've got me stumped. I've always just used the 10:1 ratio with the calculator and for water changes without any issue. Randy has revised the recipe several times, so I suppose only he could really answer. Let me do some reading and I'll get back to you.

Edit:
After some reading, I would just continue to use the 10:1 ratio unless Randy says otherwise. This ratio keeps excess chloride and sulfate ions in check, which seems to be a rather important aspect of dosing Mg salts.

[virginiadiver69]

Thanks jake.
Everything you say makes since. I'll be interested to see what Randy says.

[xJake]

Originally posted by virginiadiver69
Thanks jake.
Everything you say makes since. I'll be interested to see what Randy says.

Anytime. I think Randy mentioned something about vacation, so I'm not sure when he'll be back.

[jdieck]

Originally posted by virginiadiver69
Okay...sorry to belabor this but, I just finished reading the linked article and a couple points stood out:

"3. Using both Epsom salts and MAG flake,dissolve 7¼ cups MAG flake and ¾ cup Epsom salts in one gallon of water, and use that to supplement magnesium in amounts determined using this linked online calculator, with the entry "Randy's Recipes 1 and 2 Versions A and B," and ignore for this purpose what those designations mean.This recipe is preferred, but its advantage over recipe #2 is minimal in most cases."

The 7 1/4c and 3/4c formula looks like something more like an 8:1 ratio. Am I splitting hairs here?

It looks like doing regular 1% daily or 30% monthly water changes negates any need for Epsom salts at all.


"Note also that this recipe (#3) is different from that given in my DIY two-part recipe, because in that case more magnesium sulfate is necessary to offset the rise in chloride that is provided by both the calcium chloride and the magnesium chloride."

This makes it sound like someone that uses Randy's DIY 2 part should use the original 5:3 ratio.

That is right:

If you use two part supplements based on Sodium Bicarbonate and Calcium chloride, You should use the 5:3 ratio in the magnesium supplement.

The 10:1 ratio (actually 9.7:1 by volume) is used if you are supplementing with limewater or via a calcium reactor.

On the calculator use "Randy's Recipes 1 and 2 versions A and B" for either one. Although there is difference in the ratios of chloride to sulfate between the two formulations, the difference in magnesium content is neglegible.

To boost your newly mixed water the formulation to use depends on the other parameter that you need to boost.

IO which is high in alkalinity and low in calcium where you would use calcium chloride to boost calcium then the 5:3 formulation will be the preferred.

Salts like Tropic Marin Pro or Red Sea Salt which are usually high in calcium and low in alkalinity, were you need to use sodium bicarbonate to boost alkalinity then the preferred formulation will be the 10:1 ratio.

Remember to try keeping your increases below the 100 ppm per day.

[virginiadiver69]

Thank you very much for the explanation!

Now, I do also use limewater but, only as top off and it doesn't keep up with demand. That's what the 2 part is for. So...I'll assume the 5:3 formula is still recomended unless I'm told otherwise.

Originally posted by virginiadiver69
This recipe is preferred, but its advantage over recipe #2 ( dowflake only ) is minimal in most cases."

What about this? If I can safely eliminate the Epsom salts from the mix by doing regular water changes, which I already do, it would cut down on cost and time.

[jdieck]

If you are using two part and make regular water changes using Mg chloride only will be OK. The highest risk of chloride increase combined with the sodium from the baking soda is a slight increase in salinity over time, that will get adjusted with the water changes.

[virginiadiver69]

Thanks all for your patients and answers. I think I finally understand this now.