Dosing Magnesium Question

[denvig]

Daire
Are you sure of the accuracy of your test kit? Have you tested the NSW before adding? It would be interesting to know what it is.

 

[starrfish]

Dennis - it's the Hach test kit that I just got last month. I tested the calcium component against a Salifert kit and they were right on. I haven't specifically test the magnesium of my NSW, but EVERYTHING in my NSW is low (calc 380, sg 1.022) so it's not surprising if the magnesium is low too. There must be a fresh water outlet somewhere near where I'm collecting. There are a lot of lakes down here on the cape so I wouldn't be surprised by that either.

 

[denvig]

Oh I guess that makes sense. I was having trouble understanding the drop if you were replacing 5 gallons of water a day.

 

[Greg Hiller]

>EVERYTHING in my NSW is low (calc 380, sg 1.022) so it's not surprising if the magnesium is low too<

Just add some NSW instead of DI for evap. make up then. You should have your salinity at 1.025 at least.

> I want to start using the homemade recipe, but I don't want to overdue it. Any advice?<

Yes, read the original thread about the supplement.

I'll repost the important part for you:

>Adding this at the rate of about 10 ml/gallon of tank volume (in a stream of water where it will get mixed into the tank quickly) will increase the magnesium level in your tank by about 100 ppm. It's never a good idea to make changes too fast to a tank's water chemistry, so if your tank is low in magnesium by more than 100 ppm I'd still only add 10ml/gallon/day until you are back around 1250-1350 ppm. So, for instance, if your 100 gallon tank were 300 ppm low in magnesium, you'd need about 3 liters, or almost 1 gallon of this solution to get back into the proper range on magnesium.<

 

[starrfish]

>EVERYTHING in my NSW is low (calc 380, sg 1.022) so it's not surprising if the magnesium is low too<

Just add some NSW instead of DI for evap. make up then. You should have your salinity at 1.025 at least. <

I add salt to bring my NSW up to 1.025 when I do my water changes.

> I want to start using the homemade recipe, but I don't want to overdue it. Any advice?<

Yes, read the original thread about the supplement.

I'll repost the important part for you:

>Adding this at the rate of about 10 ml/gallon of tank volume (in a stream of water where it will get mixed into the tank quickly) will increase the magnesium level in your tank by about 100 ppm. It's never a good idea to make changes too fast to a tank's water chemistry, so if your tank is low in magnesium by more than 100 ppm I'd still only add 10ml/gallon/day until you are back around 1250-1350 ppm. So, for instance, if your 100 gallon tank were 300 ppm low in magnesium, you'd need about 3 liters, or almost 1 gallon of this solution to get back into the proper range on magnesium.<

I didn't see that detail in the original thread - I think it was contained in another thread. Thanks - helpful info!