CaSO4 & MgSO4 ratio

kizwan

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Is this look good? Ca : Mg ratio = 3 : 1. Dose 1x per week. MgSO4 already in a solution while CaSO4 will be dry dosing. For CaSO4, can I mix it with RO water in 250 or 500 ml container, shake it vigorously & poor it in the tank? Can it help dissolve in the water quickly?

MgSO4
Your addition of 200 g (equivalent to 13 tbsp + 0 tsp + 1/8 tsp + 1/16 tsp + 1/32 tsp ) MgSO4.7H2O to your 500mL container, with doses of 7mL to your 15gal aquarium adds:
Element ppm/degree
Mg 4.8627
S 6.4153
dGH 1.1225

CaSO4
Your addition of 1 tsp/caps CaSO4.2H2O to your 15gal aquarium adds:
Element ppm/degree
Ca 12.7088
S 10.1678
dGH 1.7801
 
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Allwissend

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Looks good . Personally I like having a bit more Ca for a total GH around 5 °dH for most aquariums but if it's a convenient dose for you, it will work. Btw... thanks for including the dosing results in your question. It helps a lot.

For CaSO4, it helps a bit and also helps to add in the outflow so it gets more distributed / suspended. Just don't let it settle for too long.
 
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kizwan

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I hesitate to add more considering solubility issue with CaSO4. I don't have scales to weigh in mg. Right now I have to rely on teaspoon. If CaSO4 give so much trouble, I might get CaCl2. Then I would be able to mix K2SO4+MgSO4+CaCl2 in one solution. Or is it better for K2SO4 in different container? Somehow when I do the research before getting it, I missed the information that CaSO4 is not easily dissolved in the water.
 

kizwan

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Mixing the CaSO4 in a container before pouring into tank works really well. I add one tsp of CaSO4 & RO water in a transparent 250 ml bottle. Shake vigorously & pour the solution in the tank. Like you said ([@Allwissend]) pouring near the outflow helps a lot in distributing the solution. I don't see white powder accumulating anywhere in the tank. I also tried in another tank that don't use filter, just need to manually distribute the solution to entire tank. I can see small white dot on the leaves & after a while it dissappear.

I have a question though, why some website like 2hraqurist for example only talk about magnesium (mixing dry salt)? Is this because hard water have enough Ca in it? Water in my country generally soft but information about water analysis is hard to get. The ones that only available is research paper done by universities but it is not up to date & mineral analysis result varied a lot though.
 
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Allwissend

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Glad it worked well for you. Can't really say why there is such an emphasis on Mg. Properly remineralized water will have enough Mg for at least a week, often a lot longer, so if you have RO or very soft water just remineralize. Most 'natural' hard waters will have enough Mg.

I hesitate to add more considering solubility issue with CaSO4. I don't have scales to weigh in mg. Right now I have to rely on teaspoon. If CaSO4 give so much trouble, I might get CaCl2. Then I would be able to mix K2SO4+MgSO4+CaCl2 in one solution. Or is it better for K2SO4 in different container? Somehow when I do the research before getting it, I missed the information that CaSO4 is not easily dissolved in the water.

I see this often, so worth mentioning here even if you moved past the idea. Mixing CaCl2 and MgSO4 ( or other sulfate salts eg. K2SO4) in a solution will ultimately result in the precipitation of CaSO4 (if its solubility is exceed). The ions are free to interact with each other once fully dissolved. So don't mix them in one solution. One way to make a liquid remineralizer is to stick with only chloride salts ( CaCl2, MgCl2, KCl), highly suspect some commercial products are just that.
 
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kizwan

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My plants still not recovered from curling leaves after 2 weeks of dosing CaSO4. Plants also stunted & unhealthy. Some even died. Not much more info I can give for other people other than how much I'm dosing. Sorry. Lol

KH2PO4 PO4 ~2.95 ppm / week
K2SO4 K 12.64 ppm, S 5.18 ppm / week
MgSO4 Mg 4.8627 ppm, S 6.4153 ppm / week
CaSO4 Ca 12.7088 ppm, S 10.1678 ppm / week
CSM+B Fe 0.05 ppm / week

PO4 ~2.95 ppm / week
K ~12.64 ppm / week
Ca ~12.7088 ppm / week
Mg ~4.8627 ppm / week
S ~21.75 ppm / week
Fe ~0.05 ppm / week

Have issue with red algae, so very small Fe dosing. Known deficiencies (stunted) if I stop dosing like for two weeks are PO4 & Fe. Sometimes I like to dose PO4 up to 4 ppm / week. I don't know if that helps.
 

rajkm

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What is your NO3 source?
caso4 being attributed to leaf curling is not accurate because I grow with just 2-3dGH.
ratios dont matter unless you are overdosing.
unless you have a whole lot of fish you will need a nitrate source.
focus on co2 to start with.
 

kizwan

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What is your NO3 source?
caso4 being attributed to leaf curling is not accurate because I grow with just 2-3dGH.
ratios dont matter unless you are overdosing.
unless you have a whole lot of fish you will need a nitrate source.
focus on co2 to start with.
Sorry for replying too late. My planted aquarium have been recovering. I believe it something to do with water hardness. The RO water that I use to topup water (I use fan to stabilize water temp) in the aquarium, have problem / low quality & I have stop using it. I'm pretty sure either Ca or Mg was spiking because of low quality RO water. It seems like a long journey fixing this issue, including "detoxing" the tank for a month, meaning not dosing any fert, just doing water change. Then only dosing PK & Ca+Mg with calculated ratio approximately 3:1, not exactly but close enough if ignore the decimal points number. Any dead plants have been replaced with healthy plants. Old & new leaves look beautiful & bright green color.

NO3 always high, so I did not dose any NO3. I only dose PK & Ca+Mg. I also do not dose micro/CSM+B because my tank don't need it & it only causing problem. I don't have any micro/Iron deficiency.
 
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