[wozza]

Hi all, i have today just got myself a Mg test kit as i havnt been able to get my Ca, pH and alk up past 390ppm 8.0 and 7.4 respectivly.
I thought low Mg must be the reasion...i wasnt wrong, my Mg is at 1000ppm.
I also got 250ml salifert's liquid Mg, well it turns out i need 32lts to get a 400ppm increse in 200lts as anyone can plainly see that just not gonna happen.
so i ordered some calcium hydroxide and https://www.aquaticsfanatics.com/product.php?prod=99

Is this Mg product what i need to raise my Mg, is this a good choice?

Also i could do with some advise on how, how often and when to add/dose kalkwasser.

same for the Mg product.

any advice in general about maintaing levels.

thanks james

[smpolyp]

James having low levels seems all to common these days. With a magnesium level that low it will be hard to have a balance calcium/alkalinity that most would like. I would say dosing calcium, magnesium (chloride), and an alk buffer at the same time in small amounts is best. Gradual addtions are key to help you prevent a sesaw effect. For pH you may want to wait to test after you balance cal, alk, mag. pH can be effected by other things such as co2. I would also recomend you test your newly made up seawater. Most people find one or more levels of cal, alk, mag, are lower than one would like. Also remember when you drip kalkwasser(limewater) that you do it slowly as it can impact your alk and pH levels. If it is a fully stocked tank look to other additions to help feed the coral.

[Ninong]

Originally Posted by wozza

Hi all, i have today just got myself a Mg test kit as i havnt been able to get my Ca, pH and alk up past 390ppm 8.0 and 7.4 respectivly.

When you post alkalinity numbers, you should always post the unit of measurement. In this case, you probably mean dKH and not mEq/L. In any event, all three of your numbers are within an acceptable range. The calcium could be a little higher (410 ppm is NSW Ca) but 380 ppm is acceptable. Your pH is acceptable, too. When did you measure it? That makes a big difference. If you measured it in the morning, you will find that the afternoon measurement (after the lights have been on for several hours) will be higher. Your alkalinity, assuming it's 7.4 dKH, is perfectly normal. We hobbyists prefer to maintain alkalinity in reef tanks a little higher than NSW levels but your level is absolutely normal.

I thought low Mg must be the reasion...i wasnt wrong, my Mg is at 1000ppm.

This is less than NSW Mg concentration of 1300 ppm but it is not low enough to cause problems maintaining calcium. Your Mg levels would have to drop lower than that before you would run into problems with calcium.

so i ordered some calcium hydroxide and https://www.aquaticsfanatics.com/product.php?prod=99

Is this Mg product what i need to raise my Mg, is this a good choice?

I wonder why they're including magnesium sulfate salts (epsom salts) with magnesium chloride? I don't care to add epsom salts myself. Maybe it's a cost thing? Epsom salts are very cheap.

Also i could do with some advise on how, how often and when to add/dose kalkwasser.

You should drip limewater (Kalkwasser) very slowly at night to replace evaporation. You can start out with just one teaspoon of calcium hydroxide powder per gallon of freshwater. Later on, if your calcium demand requires it, you can increase that to two teaspoons of Kalkwasser per gallon of freshwater. Two teaspoons is the most that will go into solution in a gallon of water.

same for the Mg product.

I used a magnesium chloride product only when my Mg levels dropped below my desired goal of 1300 ppm. The main thing here is to take your time. It's OK if it takes two or three weeks to get it up to 1300 ppm. Don't rush it.

P.S. -- I have never used an alkalinity buffer. Regular use of limewater (Kalkwasser) will maintain balanced calcium and alkalinity. It's balanced already. It will do nothing for magnesium levels. So, as your magnesium is depleted, you will have to bring it up with a magnesium additive, such as magnesium chloride. Using Kalkwasser will maintain stable pH, calcium and alkalinity and help to keep phosphate levels very low.

[wozza]

I would also recomend you test your newly made up seawater. Most people find one or more levels of cal, alk, mag, are lower than one would like

good idea havnt done that yet!

We hobbyists prefer to maintain alkalinity in reef tanks a little higher than NSW levels but your level is absolutely normal.

yeah i knew that they were OK but ide like them i little higher .

Two teaspoons is the most that will go into solution in a gallon of water.

its that a US gal or a UK gal?

It's OK if it takes two or three weeks to get it up to 1300 ppm. Don't rush it.

cool i will take my time then.

Using Kalkwasser will maintain stable pH, calcium and alkalinity and help to keep phosphate levels very low.

awsome thats what i like to here!

cheers and thanks for the help

[Ninong]

Originally Posted by wozza

its that a US gal or a UK gal?

U.S. gallon (3.7583 liters).

[rayjay]

For Craig Bingman's recommended magnesium suppliment as a stand alone suppliment, one mole of magnesium sulphate mixed with 10 moles of Magnesium chloride hexahydrate would give a reasonably balanced ionic additive to boost magnesium. (1 mole epsom = 1.56 and 1 mole mag chlor hex = 1.67)
He recommends 10 cups mag chloride to 1 cup of epsom.
(Also recommended by Randy Holmes-Farley when not using his DIY suppliments for Calcium, Alk, and Mag.)

[Ninong]

That makes more sense. I wonder if that's the ratio Seachem uses?

[wozza]

That makes more sense. I wonder if that's the ratio Seachem uses?

yeah wouldnt that be nice!
i will have a look at the packageing when it arrives and see if it states any ratios.