Just about to order some more EI salts am I missing anything

[RolyMo]

I am getting low on Magnesium Sulphate (MgSO4) so I thought I would investigate a top up. I notice on one site that their were different EI mixs for hard and soft water. I am very much in the hard water side.

My question is there anything else I should be adding to the mix other than:-
MgSO4
KH2PO4
KNO3
Chelated Trace

Thanks for your help.
Cheers
Roland

 

[ceg4048]

There is nothing else required really, and you may not even need to use MgSO4. Have a look at your water report and see if there is Mg in it. Try not using it for three weeks and see if you can tell the difference in growth. If not then that means you have plenty of Mg in your tap.

Cheers,

 

[bluemoon280]

How much mg is "some"?

What kind of figure in mg in my water would to be equivalent to ei dosing or half dosing for example.

I mean if its 'x' mg this would mean a reduction in dosing of "y".

Regards

 

[ceg4048]

In this case "some" means any value greater than zero.

For ease, a general value of about 1 teaspoon per 100L at water change time should do the trick. Even that amount is more than enough. If your water report specifically lists an Mg content then you probably have enough. It's only because the water reports tend to report the GH, rather than the individual Calcium and Magnesium values that tap water users need to try the Epsom Salts addition just to see if it makes a difference. RO and soft water tap users should add this unless their remineralizing agent contains Mg.

EI does NOT have a target value for Mg. Some trace element mixes such as TPN include small amounts of Mg. The amount required is so small that it's pointless getting into x and y, so if you know for certain that your tap water has Mg then just leave it, but if you don't know for sure then it's worth a try to see if there is any improvement.

Cheers,

 

[bluemoon280]

Hmmm. Thanks for the reply.

Under ei dosing. On my 750 lt tank I put in 5 tsp thrice a week. I understand you have a similar size tank. Which would equate to 15 tsp over the week. This would be twice the amount you dose.

I understand ei dosing is a suck it and see dosing method. However unlimited dosing, which is the aim of ei, seems slightly contradictory, when I can dose zero to 15 tsp a week of mgso4.

Or does it not matter, how much I dose.

In fact the more I think about it, ei seems to have an extreme range of thinking; from a ppm target that has to be aimed for and dose it if you like mentality.

I'm sure that this has been chewed over and over.

However as a 'finger in the air' guide. Am I wiser to dose mgso4 at 15 tsp a week for peace of mind.

In the event the reply is 'see what happens', how long do I wait. A week, two, a month,?

Regards

 

[bluemoon280]

I am following this ei dosing regime. Which has a significant amount of mgso4 as a percentage of the total dose. (This is for 20usg)

Sunday – 50% or more Water Change then dose [3/16 teaspoon KNO3] + [1/16 teaspoon KH2PO4] + [½ teaspoon MgSO4]
Monday – 1/16 teaspoon CSM+B
Tuesday - [3/16 teaspoon KNO3] + [1/16 teaspoon KH2PO4] + [½ teaspoon MgSO4]
Wednesday - 1/16 teaspoon CSM+B
Thursday - [3/16 teaspoon KNO3] + [1/16 teaspoon KH2PO4] + [½ teaspoon MgSO4]
Friday – Rest
Saturday - Rest


Regards

 

[ceg4048]

The reason you can dose zero to 15 tsp a week is because the guide assumes nothing about the Mg content of your water. How can we possibly know what the content of anyone's water is when, for example you don't even know what the value is for your own water? Secondly, a trace element is exactly what the word means; Trace. That means you only need a trace amount. So that's why the minimum number only has to be a non-zero number.

The guide assumes, if anything, worst case, i,e, that the hobbyists is using RO water, and that the water's Mg content is zero. Unfortunately, Mg is only a very small percentage of MgSO4. Furthermore, MgSO4 is not sold as MgSO4. It is sold as MgSO4.7H2O which is refered to as "Heptahydrate". So, because this molecule is hydrated, the percentage of Mg in this hydrated molecule is even smaller than if it were the "anhydrous" form of MgSO4.

The long and the short of it is that 10 grams (about 2 teaspoons) of Epsom Salt only has 1 gram of Mg. That's why when you assume the water has zero Mg you have to dose so much of the powder just to get a small amount of Mg. If we change the assumption and assume that your tap water already has some Mg in it, then it becomes much less important to dose large amounts of the Epsom Salt. Then of course, there is the added consideration that adding Epsom Salts increases the TDS/conductivity of the water and some people prefer to minimize the impact of GH due to special consideration for their soft water fish.

You need trial and error because of the ambiguity of the water report as well as the fact that there is a huge diversity in water nutrient content. Even in hard water there is a possibility that the GH content is 100% Calcium with no Mg. It's also possible that the GH is comprised of 100% Mg and zero Calcium. So it's not that the dosing method is contradictory, it's that we don't know what's in your water and one size cannot possibly fit all.

When you experiment with trace nutrient changes, normally 3 weeks is a good period to see any changes. That assumes of course that the changes you see in the plants are only due to the change in Mg dosing and not due to some other factor.

EI encourages you to make changes to the dosing levels and to see the effects. It is an interactive procedure and does not rely on one size fitting all. What you see as "finger in the air" we see as systematic, flexibility and optimization.

See more details and calculations in the thread Epsom Salts | UK Aquatic Plant Society

Cheers,

 

[bluemoon280]

Thanks for the clarification. I was unaware of the low mg content in the salt.
Regards