Fluval Sea Magnesium Additive

FugeTown · Nov 26, 2016

Just purchased a bottle of Fluval Sea Magnesium additive and was wondering if anyone has tried it out since I found zero creditable feedback about it online. It says the guarantee analysis of Magnesium is 75,000 mg/L and it claims that 5ml a per 20us gal a week will add 5 mg of magnesium to your system. I know the fluval bottle is small at a total of 8 oz but I want to know has anybody actually used this product and did it keep your Magnesium level in check?

Randy Holmes-Farley · Nov 27, 2016

My DIY recipe comes out at 47,000 mg/L, but the ingredients are very soluble and I'd expect one can reach 75,000 mg/L without a problem. So there's no reason it can't do what it claims.

That said, I'd not seen any independent analysis of it.

To determine doses and amounts, us this calculator:

http://reef.diesyst.com/chemcalc/chem_calc3.html

use the entry for Randy's DIY magnesium, and multiply the amount needed by 0.63

FugeTown · Nov 27, 2016

Thanks for the calculator link I will use that for my dosing. I ordered a salifert Magnesium test kit last night so I'll be able to monitor the level of magnesium in the water. I will post my experience with Fluval Sea Magnesium once I used it long enough to determine how good it works.

Randy Holmes-Farley · Nov 28, 2016

OK, sounds good.

Happy Reefing.

FugeTown · Dec 20, 2016

Fluval Sea Magnesium update

Tested Magnesium with salifert test kit
Magnesium level - 1380
Tank size-40 gallon breeder

Added 10ml of Fluval Sea Magnesium
Magnesium level after dose- 1400

N2theUnknown · Jan 26, 2022

Randy Holmes-Farley said:
My DIY recipe comes out at 47,000 mg/L, but the ingredients are very soluble and I'd expect one can reach 75,000 mg/L without a problem. So there's no reason it can't do what it claims.

That said, I'd not seen any independent analysis of it.

To determine doses and amounts, us this calculator:

http://reef.diesyst.com/chemcalc/chem_calc3.html

use the entry for Randy's DIY magnesium, and multiply the amount needed by 0.63

Hey quick few questions on this topic.

1. This calculator is saying I need 419ml of this product. If I have 55 US GAL curent mag is 1200 and I want to gwt it to 1350.
This seems like alot am I missing something or is this correct?

2. How much can you raise mag at once without ill effect? Everything I have read says 100ppm. Obviously I will does this out throught the next week or so but juat for curiosity.

Thanks for your time and help!