Hello from the uk. Looking for a homemade iron supplement please anybody got one? I currently use the vita med tablet but my tank uses 5ml a day. Wanting something I can make a litre at a time.
Last edited:
Homemade iron supplement
- Thread starter Frag_mad
- Start date
- Tagged users None
Randy Holmes-Farley
Reef Chemist
Staff member
Super Moderator
Excellence Award
Expert Contributor
Article Contributor
R2R Research
My Tank Thread
I have DIY recipes using Fergon iron tablets, and iron-based chemicals depending on what you can buy there.
One Fergon tablet (ferrous gluconate) contains 27 mg of iron. Dissolve that in about 27 mL RO/DI (my recommendation, but other concentrations are OK, just don't dilute too much), the concentration is about 27 mg/27 ml ~ 1 mg/mL.
I dose ~1 mL to my tank with a volume of about 300 gallons ) once or twice a week.
One Fergon tablet (ferrous gluconate) contains 27 mg of iron. Dissolve that in about 27 mL RO/DI (my recommendation, but other concentrations are OK, just don't dilute too much), the concentration is about 27 mg/27 ml ~ 1 mg/mL.
I dose ~1 mL to my tank with a volume of about 300 gallons ) once or twice a week.
Randy Holmes-Farley
Reef Chemist
Staff member
Super Moderator
Excellence Award
Expert Contributor
Article Contributor
R2R Research
My Tank Thread
FYI, you can make that in higher amounts or more concentrated.
Most people cannot buy good quality laboratory chemicals, but long ago i did give a recipe using ferrous sulfate:
Chemistry And The Aquarium: Iron In A Reef Tank
Randy discusses iron and its usage in our aquariums.
reefs.com
from it:
Iron in Reef Tanks: How Much and What Form?
Deciding how much iron to add is fairly easy because, in my experience, it doesn’t seem to matter too much. Presumably, once you add enough to eliminate iron as a limiting nutrient, extra iron does not apparently cause harm (at least that I’ve detected in my tanks or heard of from others). I selected a dose of about 0.1 to 0.3 mL of a solution containing 5 g of iron (as 25 g of ferrous sulfate heptahydrate) in 250 mL of water containing 50.7 g of sodium citrate dihydrate. This liquid is dosed 2-3 times per week to my system with a total water volume of about 250 gallons. This iron(II) citrate has turned brown and cloudy since I first made up the bottle years ago, suggesting that it is oxidizing to iron(III) and some is precipitating from solution, but I still use it. Over the past 4 years, I’ve dosed nearly all of the 5 grams of actual iron to my tank.
Now that may sound like a huge amount, and it is. It’s enough to bring 800 million gallons of completely depleted seawater up to the 0.000006 ppm level that I mentioned earlier for natural sea surface water. Still, I’ve not noticed any problem, do not know the steady state concentration, do not know how high of a solution concentration is actually optimal for my tank, do not know how much is biologically available by the mechanisms mentioned below, do not know how fast it is removed by skimming and other mechanisms, and do not know what would happen if I cut it back by a factor of 1,000.
All that I know is that microalgae has never been a problem since starting the iron, and I’ve not noticed anything negative that I could attribute to the iron (nor have I heard of any from others doing similar dosing). Still, I don’t keep all organisms available to the hobby, and if you do seem to get a negative reaction from something, I’d advise backing off on the dose or stopping completely.
Since many hobbyists do not have access to the chemicals required to make iron(II) citrate, I’d advise buying a commercial iron supplement. There are a number available that seem appropriate and are not very expensive. Some commercial supplements combine manganese with iron (such as Kent’s product), presumably because the scientific literature has demonstrated that phytoplankton also scavenge manganese from the water column. I’ve not experimented with manganese, but it is probably fine to use if you cannot find a pure iron supplement.
I’d also advise using only iron supplements that have the iron chelated to an organic molecule. The iron sold for freshwater applications is sometimes not chelated because free iron is more soluble in the lower pH of freshwater tanks. I’d avoid those products for marine applications. It will likely still work (as many of the studies in the scientific literature use free iron in seawater), but probably not as well because it may precipitate before it has fully fortified the system with iron.
In many cases of iron intended for the marine hobby, the product may not tell you what the iron is chelated with, in order to protect proprietary formulations. I don’t actually know if it matters too much. Very strong chelation by certain molecules will actually inhibit bioavailability by not permitting release of the iron without completely taking apart the chelating molecule, but I expect that manufacturers have avoided those molecules. EDTA and citrate, and some others, actually degrade photochemically, releasing small amounts of free iron continually. It is believed to be the free iron that is actually taken up by many organisms, and likely iron(II), though some organisms may be able to convert iron(III) to iron(II) before uptake (the detailed absorption mechanisms are generally not known). There is a more detailed discussion of this degradation and uptake in “Captive Seawater Fishes” by Stephen Spotte (1992).
FYI, you can make that in higher amounts or more concentrated.
Most people cannot buy good quality laboratory chemicals, but long ago i did give a recipe using ferrous sulfate:
Chemistry And The Aquarium: Iron In A Reef Tank
Randy discusses iron and its usage in our aquariums.
from it:
Iron in Reef Tanks: How Much and What Form?
Deciding how much iron to add is fairly easy because, in my experience, it doesn’t seem to matter too much. Presumably, once you add enough to eliminate iron as a limiting nutrient, extra iron does not apparently cause harm (at least that I’ve detected in my tanks or heard of from others). I selected a dose of about 0.1 to 0.3 mL of a solution containing 5 g of iron (as 25 g of ferrous sulfate heptahydrate) in 250 mL of water containing 50.7 g of sodium citrate dihydrate. This liquid is dosed 2-3 times per week to my system with a total water volume of about 250 gallons. This iron(II) citrate has turned brown and cloudy since I first made up the bottle years ago, suggesting that it is oxidizing to iron(III) and some is precipitating from solution, but I still use it. Over the past 4 years, I’ve dosed nearly all of the 5 grams of actual iron to my tank.
Now that may sound like a huge amount, and it is. It’s enough to bring 800 million gallons of completely depleted seawater up to the 0.000006 ppm level that I mentioned earlier for natural sea surface water. Still, I’ve not noticed any problem, do not know the steady state concentration, do not know how high of a solution concentration is actually optimal for my tank, do not know how much is biologically available by the mechanisms mentioned below, do not know how fast it is removed by skimming and other mechanisms, and do not know what would happen if I cut it back by a factor of 1,000.
All that I know is that microalgae has never been a problem since starting the iron, and I’ve not noticed anything negative that I could attribute to the iron (nor have I heard of any from others doing similar dosing). Still, I don’t keep all organisms available to the hobby, and if you do seem to get a negative reaction from something, I’d advise backing off on the dose or stopping completely.
Since many hobbyists do not have access to the chemicals required to make iron(II) citrate, I’d advise buying a commercial iron supplement. There are a number available that seem appropriate and are not very expensive. Some commercial supplements combine manganese with iron (such as Kent’s product), presumably because the scientific literature has demonstrated that phytoplankton also scavenge manganese from the water column. I’ve not experimented with manganese, but it is probably fine to use if you cannot find a pure iron supplement.
I’d also advise using only iron supplements that have the iron chelated to an organic molecule. The iron sold for freshwater applications is sometimes not chelated because free iron is more soluble in the lower pH of freshwater tanks. I’d avoid those products for marine applications. It will likely still work (as many of the studies in the scientific literature use free iron in seawater), but probably not as well because it may precipitate before it has fully fortified the system with iron.
In many cases of iron intended for the marine hobby, the product may not tell you what the iron is chelated with, in order to protect proprietary formulations. I don’t actually know if it matters too much. Very strong chelation by certain molecules will actually inhibit bioavailability by not permitting release of the iron without completely taking apart the chelating molecule, but I expect that manufacturers have avoided those molecules. EDTA and citrate, and some others, actually degrade photochemically, releasing small amounts of free iron continually. It is believed to be the free iron that is actually taken up by many organisms, and likely iron(II), though some organisms may be able to convert iron(III) to iron(II) before uptake (the detailed absorption mechanisms are generally not known). There is a more detailed discussion of this degradation and uptake in “Captive Seawater Fishes” by Stephen Spotte (1992).
Hi randy. Thanks for the help. I've purchased last week the 300mg tablets in the uk, upon looking today there seems to be a new vita med tablet and rather than the 300mg ferrous fumarate which approximates 35mg of elemental iron, the new ones seem to be 200mg ferrous sulphate claiming 64mg elemental iron. How would I adjust the recipe? Thanks
Randy Holmes-Farley
Reef Chemist
Staff member
Super Moderator
Excellence Award
Expert Contributor
Article Contributor
R2R Research
My Tank Thread
Same recipe. Iron doses are far from critical.
Ferrous sulfate lacks the chelating organic to help keep it in solution as it oxidizes to ferric iron (which is pretty insoluble in seawater), but it will still be useful to dose since the iron will bind to organics in the water.
Randy Holmes-Farley
Reef Chemist
Staff member
Super Moderator
Excellence Award
Expert Contributor
Article Contributor
R2R Research
My Tank Thread
Randy Holmes-Farley
Reef Chemist
Staff member
Super Moderator
Excellence Award
Expert Contributor
Article Contributor
R2R Research
My Tank Thread
No.
27 mg in 27 mL is 1 mg/mL.
Add 1 mL of that (containing 1 mg) to 1 gallon (3.78 L) adds 1 mg/3.8 L = 0.26 mg/l ~ 0.26 ppm
That's also a huge dose. You would not want to add that much (IMO).
27 mg in 27 mL is 1 mg/mL.
Add 1 mL of that (containing 1 mg) to 1 gallon (3.78 L) adds 1 mg/3.8 L = 0.26 mg/l ~ 0.26 ppm
That's also a huge dose. You would not want to add that much (IMO).
cyclone11
New Member
Hi Randy can you help since fergon is not available at my country, can I use Mason Natural Ferrus Gluconate as a substitute for fergon, if it is can I used the same computation as fergon in mason?
Randy Holmes-Farley
Reef Chemist
Staff member
Super Moderator
Excellence Award
Expert Contributor
Article Contributor
R2R Research
My Tank Thread
Yes, that material seems reasonable and the calculation is the same. 
cyclone11
New Member
Thanks RandyYes, that material seems reasonable and the calculation is the same.
cyclone11
New Member
Yes, that material seems reasonable and the calculation is the same.
Randy Holmes-Farley
Reef Chemist
Staff member
Super Moderator
Excellence Award
Expert Contributor
Article Contributor
R2R Research
My Tank Thread
You're welcome.
Happy reefing.
Happy reefing.
Randy Holmes-Farley
Reef Chemist
Staff member
Super Moderator
Excellence Award
Expert Contributor
Article Contributor
R2R Research
My Tank Thread
They are probably ok. Put a pill in di water, let it crumble naturally and then shake it briefly, let it settle, and use the clear colored liquid, leave the solids behind.
Randy Holmes-Farley
Reef Chemist
Staff member
Super Moderator
Excellence Award
Expert Contributor
Article Contributor
R2R Research
My Tank Thread
You’re welcome.
Happy Reefing!
Happy Reefing!
Similar threads
