@nilocg and
@Zorfox thank you very much for your responses and corrections. It seems my logic replaced my memory …more on this later but first I was able to find some statement Barr made on this topic:
GH range 3 degrees ~ 50ppm or higher
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You can use SeaChem Equilibrium for this or a mix of CaCl2 (or CaSO4 although it is not as easy to dissolve into water) and MgSO4 at a 4:1 ratio to increase GH. You can add this without knowing what your GH is by adding 1 degree's worth after a weekly water change (or slightly less with less frequent water changes)
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If you also add the GH booster suggestions in this, then you will have a higher range of K+, about another 10-20ppm.
Source: Tom Barr on
The Estimative Index of Dosing, or No Need for Test Kits - Aquarium Plants - Barr Report
From this I understand the following:
When re-mineralizing you should target a level of at least 3 degrees (assuming °dGH)
As a fertilizer, it should add about 1 °dGH. The mix is also meant to increase the K+ by 10-20ppm in addition to the 20-30ppm coming from other fertilizers used.
You might consider making your own from the base chemicals.
2 parts: K2SO4: potash of sulfur
1 part: CaSO4: Gypsum
1 part: MgSO4 Epsom salt
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GH booster is nothing more than CaSO4, MgSO4, K2SO4 and was just DIY SeaChem Equilibrium which had been used to add GH to ur soft water and was the trend in the 1990's, we added lots of K+ to every tank.
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In general, I keep about the same NO3 as I do K+ , maybe a little higher for K+
the Ca++ is the least of the issue/reason to add Gh booster, more for K+/Mg really, but a little Ca++ just in case.
Source: Tom Barr comments on
GH booster Europe - Aquarium Plants - Barr Report
Here Barr states that the GH Booster is based and meant to be similar to Seachem Equilibrium. Additionally that the K+ ppm are targeted to be similar to NO3- or “a little higher” and that the GH booster is added more for Mg++ and K+
A ratio without a type/unit tells you nothing
1 : 3 : 1 : 2 rice : water : flour : potato –>meaningless
Presuming a unit/type of measurement can lead to severe problems and given the weird preference of measuring the weight of salts with teaspoons present on that and this site… who can tell. But thanks to nilocG we know this is actually a mass ratio.
I make the gh booster using 3:3:1 by weight
But wait, it seems like somebody did something to the pooch and missed the targeted ratios…
Barrand aquariumfertilizers.com suggest a mass ratio of
3:3:1 CaSO4: K2SO4:MgSO4
Whereas most of us (even the producers?) will use the chemicals described by Zorfox
First off, your mixture is perfectly fine. That's Barr's GH booster.
Actually, Tom Barr suggested mixing CaSO4.2H2O (3 parts) , K2SO4 (3 parts) , and MgSO4.7H2O (1 part). Then use to maintain a GH of 3-5.
I have to disagree, that is not the GH booster as suggested by Barr. Barr actually suggested
3:3:1 CaSO4 : K2SO4 : MgSO4 – meaning a mass ratio of 4.4 : 6.7 : 1 Ca : K : Mg
But what we get is
3:3:1 CaSO4.2H2O : K2SO4 : MgSO4.7H2O – meaning a mass ratio of 7 : 13.7 : 1 Ca : K : Mg
For reference the Seachem Equilibrium has a mass ratio of
3.33 : 8.1 : 1 Ca : K : Mg
Hoagland solution is 4:1 (Ca:200 ppm , Mg:48 ppm) of elemental Ca and Mg. :icon_idea
Now how is that for a change in ratios due to simply ignoring the hydration level. Are the manufacturers using anhydrous salts ? Unlikely.
So it seems pretty clear to me that the plan was to get close to 4:1 or 3:1 Ca:Mg ratio but at one point the hydration levels were ignored. The ratio itself does not need to be spot on for aquatic plants but 7:1 Ca:Mg is too much Ca. This becomes a problem when you target a low GH environment , such as for fancier shrimps as you are either under-dosing Mg or increasing the TDS without reason.
One concern I have tho is the amount of K I'll be dosing. I dose kno3 and kh2po4 so my K will be up around 58.83ppm of K including the GH booster. Seems abit high?
It's funny you should mention the extra potassium (K). Of all the nutrients, potassium is probably the safest to overdose. You would have no issues even at 100ppm of potassium.
And by re-mineralizing with this GH Booster (hydrated edition) you can easily go over 100ppm K+. Given 50% weekly water change and extra K from KNO3 you will be above 300ppm K+.
Let us also look at what happens when you try to use GH Booster (hydrated edition) as a remineralizer to get to a decent 5 °dGH .
82ppm Ca
158ppm K
12ppm Mg
How is the 158ppm K in line with Barr’s recommended use of adding 10-20ppm K from the GH Booster. What about his idea of keeping the ppm of K about the same or “a little higher” as NO3- ? Something, somewhere went wrong.
It seems clear and rational that the main use of the GH Booster is mainly to make sure enough Mg is present and does not bottom out. Indeed, most Trace mixes provide some Mg and K but no Ca. The GH Booster mix with the hydrated salts focuses instead on adding a lot of Ca and way up there K. In my opinion this makes it unsuitable for remineralization and to be avoided for all applications where a low TDS is needed.
So I should ditch the mix I made and get some more chemicals?
I put coral sand in my canister filter a few weeks back to buff my calcium and I dose 11g of Epsom salts at water change. My tank GH is 8 and KH 4. Do you think it's even worth dosing a booster with the coral and mg I already add?
I've noticed my growth is abit stunted (mostly on rotala stems) but only on the new growth.
Is my problem most likely calcium and mg?
I would keep the mix and dose to reach my target Ca level than add extra Mg source to reach the originally desired 4:1 ratio. Mix the bag well before dosing so that the salts are somewhat uniformly distributed.
With the filter setup you describe I would not worry about Ca but actually dosing gives you more control. Unlikely the rotalas are stunted because of Ca or Mg.