Magnesium in a Reactor

[baldyguy]

Guys I have heard of Mg being added to a Ca reactor in granular form or crystals to add as well as Ca............anyone heard of this, what type of make and where from? Bear in mind I am in the UK, so maybe over seas ordering is the case.

 

[ccCapt]

I never heard anyone doing that and IMO, it would be almost impossible to mix them in the proper ratio that they are used (aprox 2 ppm mag for every 18 ppm calcium used).

 

[baldyguy]

Many thanks for the reply...... however, I have read that Dolomite added to the reactor will produce Mg......... add only 10% Dolomite though. Anyone heard at that one?

 

[CaptainAhab]

'
[FONT=Times New Roman, Times, serif]It has been suggested that adding dolomite to CaCO3/CO2 reactors can help with magnesium problems. Dolomite is a material that contains both magnesium and calcium carbonate. If dolomite is being added to the reactor to maintain existing appropriate magnesium levels against the continual depletion via calcification (for example, if the calcium carbonate being used is too low in magnesium to maintain adequate magnesium) then this is a fine approach. [/FONT]
[FONT=Times New Roman, Times, serif]However, this method is unsuitable if the goal is to raise magnesium levels. The problem is that for every magnesium ion released from the dolomite, 2 units of alkalinity are also released:[/FONT]

[FONT=Times New Roman, Times, serif]MgCO3

Mg++ + CO3--[/FONT]​

[FONT=Times New Roman, Times, serif]Consequently, if one wants to raise magnesium by 100 ppm, the alkalinity will necessarily rise by 8.2 meq/L (23 dKH). The only way around this problem is to add a mineral acid (not vinegar) to the aquarium to reduce the alkalinity, and that may be more problematic than just adding magnesium in the first place.'[/FONT]


[FONT=Times New Roman, Times, serif]http://www.advancedaquarist.com/issues/oct2003/chem.htm
[/FONT]

 

[baldyguy]

Totally understand what you are saying and yes i would be to maintain my Mg level and not to increase it........ i have liquid Mg at the moment and if i were to wish to increase it i would dose it accordingly.

 

[CaptainAhab]

You have that much Mg depletion that you need continual replenishment? Looking at your 'My Tanks' I never would have thought that. Perhaps your brand of salt is ultra deficient in Mg?

By continual I mean reactor vs a dosing/water change schedule

 

[baldyguy]

I have not suffered Mg depletion as I am dosing with Mg. My salt is Red Sea reef ready so I assume that it is a good? brand. The problem I have is mainly evaporation so am topping off more than most maybe? I do PWC once every 4 weeks as 10% is 130ltrs, due to the size hence the dosing etc etc........ my original query was can it be added....has anyone done it.....is there a benefit? You are correct however my levels very rarely fluctuate that bad, just trying to avoid spending a fortune on bottles that go in nearly a treatment when a solution maybe to add to my Ca reactor.

 

[CaptainAhab]

OK, I'll leave you to get what you asked answered. If I was to continue the conversation I might as why you'd buy bottles of Mg when you could buy Epsom Salts for the same thing.. and mention that replacement for evaporation should be only pure water (as that's all the evaporates).. But I won't cause I don't use Dolomite in a reactor.

 

[baldyguy]

No i can assure you it is not a problem i would rather have someone with alot more experience than me pose a question to get me thinking rather than bumbling along quite happy thinking everything is rosie........ I top of with a RO water adding some KH minerals to replace what is lost. Regards.