Hi everyone,

I have very soft water, and my plants have shown Magnesium deficiencies in the past, so I have started dosing MgSO4. Now I want to start "dosing" calcium aswell.

So, I'm making my own GH builder. As Mg source, I have some EPSON salts (MgSO4.7H2O), as Ca source, I was thinking of using hydrated plaster (CaSO4.2H2O).

I'll mix 100g of plaster and 75 g of epson salts and mill it in a planetary mill. This would yield very fine, homogeneous powder with a ratio of aprox. 2:1 in GH degrees (Ca:Mg), if I've got the calculations right. Is this a good ratio?
Then, I would dose the powder directly in the water changes, 1 gram of the mix per 10 L of water = 3GH

Do you think that plaster is OK (the kind used in buildings)? What are other cheap sources i could use?
Should I add any other element to my GH mix?

PS, I also dose macros, Flourish and iron.

Thanks,
Bode.

Should be fine.
3:1 is a bit better ratio perhaps, but you could not tell the difference in these ranges.

Regards,
Tom Barr

OK, thanks, Tom.

Hi! How about if I'll use calcium sulfate tablets (purchased in drugstores)? Should I just grind it to powder form and follow the same ratio? I plan to make a premade solution and mix it in 500g water, how much do I need of each? Thanks!

I don't think a liquid pre-mix of a "GH booster" will work out well. It is hard to get calcium compounds to fully dissolve, even in the aquarium. Trying to get enough dissolved into 500 ml of water to be able to dose even 100 ml at a time would be difficult. The Epsom salts would dissolve ok, but calcium would be a problem.

I also find it hard to believe that buying calcium sulfate tablets at a drug store could ever be economical compared to buying plaster of paris, for example. I suspect just buying "Barr's GH Booster" would prove to be a lot cheaper. When I looked at this several years ago I was surprised to find that even epsom salts, at the drug store, would cost me more than MgSO4 from Greg Watson. So, if saving money is the reason for the DIY, be sure to actually check the costs first.

Hi sir. I wish I could simple make an online order for GH booster, problem is that I lived in a different country and the shipping cost would cost a fortune. If making a pre-mix will be troublesome, can I just dose them separately to achieve the same effect of GH booster? thanks again!

You folks have agriculture there right?
Most countries have that. So they generally sell things like Gypsum, Epsom salt, potash of sulfur etc.

Mix some up, add to the tank.
Tracking it down might be an issue, but once you do, you'll have a life's supply.

About 50% of the folks here are from somewhere other than the USA.


Regards,
Tom Barr

If you can mix the powdered ingredients together without a problem, that is a good way to go. My comment was only in reference to making a liquid premix. I have tried to mix Seachem Equilibrium with water before adding it to the tank, and it just doesn't work. I end up mixing it as best I can, pouring off the milky looking water, adding more water and shaking it more, pouring off the less milky looking water, adding more water and just swirling it around so I can dump the whole thing, undissolved particles and all into the tank. And, this was with, as I recall, one half a teaspoon of Equilibrium in about 500 ml of water. My conclusion was that GH builder has to be dosed dry.

Hi sir. Yup, that's exactly what my first reply to this post was all about. The materials/chemicals I have right now:

Magnesium Sulphate
Potassium Sulphate
Calcium Sulfate Tables

I just don't know how much of each should I mix in the solution and how to dose for a 50g tank.

I think I've a similar scenario when I tried dissolving calcium sulfate tablets in water and adding it to my tank. It went cloudy for several hours. As long as it won't harm anything I think I can live with that. I dose during lights off so the water has enough time to clear before lights on. Thanks for the reminder.