# Magnesium do I need to add?



## Robert Fletcher (1 Feb 2018)

My water supply has
GHd 9.84
Magnesium 11.06 ppm
Calcium 54.1 ppm

Do I need to add MgSO4 to the macros or is the supply sufficient sufficient?


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## Edvet (1 Feb 2018)

Should be sufficient if you do large waterchanges to replenish Mg.


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## ian_m (1 Feb 2018)

I would just add standard EI dose of MgSO4, it is cheap and you can't over dose. Therefore no need to worry about your water report. Done.


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## Robert Fletcher (1 Feb 2018)

Edvet said:


> hould be sufficient if you do large waterchanges to replenish Mg.


 Thank you for that I do 50% weekley


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## Robert Fletcher (1 Feb 2018)

ian_m said:


> I would just add standard EI dose of MgSO4, it is cheap and you can't over dose. Therefore no need to worry about your water report. Done.


I have gone over the the EI calculator and the MgSO4 Magnesium is added by way of GH Boost "Only if needed". As Edvet said no need as long as I do the WC which I do. Thanks.


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## mow said (1 Feb 2018)

11.06 ppm is enough magnesium


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## ian_m (1 Feb 2018)

I don't know where you got your water report from, but if you are Leicestershire if is highly unlikey you have any Mg in your water.

See here for why.
https://www.ukaps.org/forum/threads/switched-to-ei-what-went-wrong.39438/page-2#post-492462

So just dose MgSO4 as part of EI regime. No worry. Done.


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## Robert Fletcher (1 Feb 2018)

ian_m said:


> I don't know where you got your water report from, but if you are Leicestershire if is highly unlikey you have any Mg in your water


STW did the check today on my line. I will accept the professionals analysis.


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## ian_m (1 Feb 2018)

Robert Fletcher said:


> STW did the check today on my line. I will accept the professionals analysis.


Anyway, I would still add MgSO4, as cheap. Then no worrys about lack of Mg. I would say in virtually 100% of the cases here where people roll their own dosing scheme, the plants end up suffering. Mg is the favourite one to miss, plants loose lose green, turn yellow (similar to iron) but recover when Mg is added, unlike iron deficiency.


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## dw1305 (1 Feb 2018)

Hi all, 





Robert Fletcher said:


> I have gone over the the EI calculator and the MgSO4 Magnesium is added by way of GH Boost "Only if needed".


That is really for Americans with soft water, there limestones tend to contain magnesium as well as calcium. There is an explanation in the link @ian_m posted.

<"Magnesium is essential for plant growth">, but they only need a limited amount. 





Robert Fletcher said:


> STW did the check today on my line. I will accept the professionals analysis.


I think there could be some magnesium in your tap water, it depends how close Hinckley is to the dolomite and or evaporite deposits on the geological map.






cheers Darrel


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## HiNtZ (5 Feb 2018)

If those are the true values (probably not) then they are pretty spot on. Are your plants showing any symptoms of Mg deficiency? Or chlorosis?

You can add a bit to see if there are any improvements, it won't harm.


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## Robert Fletcher (5 Feb 2018)

This all came about when I moved from the EI formula by Aquarium Plant Food UK to the table compiled by TNC. I like that as it gives more detail and flexibility. TNC told me the magnesium comes from GH Boost only if needed. As there was not a breakdown of calcium and magnesium I asked for the Mg levels. They rang back after a couple of days. I would sooner do that than to buy a test kit for one reading and I would always trust a proffessional chemest over anateur results. Its all free too or at least is what I pay my water charges for. Plants are all healthy.


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## HiNtZ (5 Feb 2018)

Robert Fletcher said:


> This all came about when I moved from the EI formula by Aquarium Plant Food UK to the table compiled by TNC. I like that as it gives more detail and flexibility. TNC told me the magnesium comes from GH Boost only if needed. As there was not a breakdown of calcium and magnesium I asked for the Mg levels. They rang back after a couple of days. I would sooner do that than to buy a test kit for one reading and I would always trust a proffessional chemest over anateur results. Its all free too or at least is what I pay my water charges for. Plants are all healthy.



I discussed this only recently, thanks to some members we broke it down mathamatically what TNC GH boost adds in the way of Mg, Ca and K

https://www.ukaps.org/forum/threads/tnc-gh-boost.51553/


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