Liquid GFO...

[Reefer40b]

Here is my understanding,
So I have been reading around and I come across some people that use Iron to control their phosphates, instead of using GFO in a reactor. With this method your not wiping out your phosphates to zero and able to keep them much more stable at whatever level you choose.

My only issue is I can't seem to find or don't know exactly what I'm looking for to make a Iron Citrate solution(Fe++ and Fe+++)Hydoxide:

In theory the solution should work instantly in the water column
The Fe(OH)3 will exchange his OH1- ion with PO43- , 3x OH1- released 1x PO43- ion is being absorbed.
Fe(OH)3 + PO43- => FePO4 + 3OH1-
FePO4 is precipitated and will be skimmed off, or filtered out by the filters. It should be recognized by rust (orange) color in the filter wool and in the skimmer.Possible you would see some haze at first starting out but it would clear probably in a couple of hours.

So to sum all of this up short and sweet the P04 will bond with the Iron and will then precipitate out, filter catches all the precipitate, no more buying and changing GFO or cleaning a reactor out.

Looking for ingredients sources and amounts to add to make a solution, chemistry people out there I need your expertise.

 

[ReefsandGeeks]

how is this any different in principle to lanthalum chloride (aka Phosphate Rx)? That you dose into the tank and it precipitates the phosphate out just the same way (as far as I can tell) as the method you mentioned. I don't know if your method is cheaper, or works better, but unless you have long term phosphate issues I don't think the lanthalum chloride is very expensive.

 

[dartier]

I plan to experiment with this technique as well. Glenn Fong is the person who is credited with pioneering this technique. However he has not shared his specific formula for his Iron solution. I have the raw chemicals on hand and plan to use Randy's recipe (http://www.advancedaquarist.com/2002/8/chemistry) as a starting point and then tweak the ratio to adjust the amount of Fe that is chellated with the citrate. My gut feeling is that Fe++ that is not fully chellated is involved with precipitating the PO4.

In relation to Lanthium Chloride, the same cautions apply with using the Iron solution as do to using Lanthium. The precipitate can cause issues for tangs and other fish with fine gills. Again the dust that is formed from the reaction should be filtered and removed from the tank.

Dennis

 

[Reefer40b]

how is this any different in principle to lanthalum chloride (aka Phosphate Rx)? That you dose into the tank and it precipitates the phosphate out just the same way (as far as I can tell) as the method you mentioned. I don't know if your method is cheaper, or works better, but unless you have long term phosphate issues I don't think the lanthalum chloride is very expensive.

I actually did not know about this product, and im sure it would probably not be very expensive on a smaller tank but Im sure a larger tank this may get expensive not practical.

I plan to experiment with this technique as well. Glenn Fong is the person who is credited with pioneering this technique. However he has not shared his specific formula for his Iron solution. I have the raw chemicals on hand and plan to use Randy's recipe (http://www.advancedaquarist.com/2002/8/chemistry) as a starting point and then tweak the ratio to adjust the amount of Fe that is chellated with the citrate. My gut feeling is that Fe++ that is not fully chellated is involved with precipitating the PO4.

In relation to Lanthium Chloride, the same cautions apply with using the Iron solution as do to using Lanthium. The precipitate can cause issues for tangs and other fish with fine gills. Again the dust that is formed from the reaction should be filtered and removed from the tank.

Dennis

Indeed Dennis I did read this from Glenn, also some talk with others. I think it is great that your experimenting please keep us update with some of your results. If you already have a thread somewhere I would love a link to see what you have so far. Also it would be cool if Randy could shed some light, from the threads I read he seems to know his chemistry!

 

[bertoni]

Ferric phosphate is at least somewhat toxic, and it's fairly soluble in fresh water. I don't know how soluble it is in saltwater, but it is used to kill mollusks and snails. Iron(2) phosphate (ferrous phosphate) would precipitate. I suspect that dosing iron is safe enough, though, on average. I am not sure what the advantage would be, as compared to lanthanum.

 

[Dan_P]

Fe(II) is a nutrient and wonder under what conditions and concentrations it will stimulate cyanobacteria and algae growth.

 

[Dan_P]

A few more thoughts...

If I understand what is being sggested, chelated iron (II) is dosed and it combines with phosphate, maybe near quantitatively because of the poor solubility of the phosphate salt Fe3(PO4)2. Any of the iron(II) phosphate salt not removed from the aquarium can be oxidized to two molecules of iron(III) salt FePO4 and iron oxide, both very insoluble, but possibly not biologically inert once it gets in the sand bed, possibly releasing PO4 and iron (II).

If I were developing an understanding of this technique, I would see what happens to 1 gallon sample of aquarium water that contains phosphate in a glass container. I would also monitor the iron and phosphate concentrations in the 1 gallon experiment every 15-30 minutes to understand the kinetics of the reaction and ensure the ratio of iron to phosphate being used meets expectation in terms of residual iron after the phosphate is removed. I might also expose a coral to a small amount of the precipitate and observe its reaction.

Good luck.

 

[jason2459]

Yes, increasing iron will help anything that is iron limited. This could be cyano, algae, dinoflagelets, etc. Which includes corals as the zooxanthellae in them are dinoflagelets as well.

 

[jason2459]

There's also a concern of to much iron as with any metals.

Yes, feeding pests could be a concern.

The mechanism of action is presumably precipitation of solid particles of iron phosphate, or iron hydroxide/oxide that incorporates phosphate. The knock on dosing simple iron sulfate for iron supplementation is precipitation. But that precipitation forms small particles of iron oxide/hydroxide, and so is essentially making GFO in situ.

One concern is the relatively high levels of available iron. Iron is not always a benefit, even to pests. it can facilitate something called Fenton chemistry where tissue can be oxidatively damaged:

https://en.wikipedia.org/wiki/Oxidative_stress

"Metals such as iron, copper, chromium, vanadium, and cobalt are capable of redox cycling in which a single electron may be accepted or donated by the metal. This actioncatalyzes production of reactive radicals and reactive oxygen species.[67] The presence of such metals in biological systems in an uncomplexed form (not in a protein or other protective metal complex) can significantly increase the level of oxidative stress. These metals are thought to induce Fenton reactions and the Haber-Weiss reaction, in which hydroxyl radical is generated from hydrogen peroxide."

On heavy metal issues

http://scialert.net/fulltext/?doi=rjes.2009.96.102

Heavy Metal Levels and Their Potential Toxic Effect on Coral Galaxea fascicularis from Java Sea, Indonesia



A. Sabdono

ABSTRACT
Specific aims of the study were to quantify heavy metal concentration in the coral tissue and to determine the toxic effect of metal on coral Galaxea fascicularis. The concentration of heavy metals in the coral tissues were assessed using Atomic Absorption Spectrophotometer (AAS) technique. Various oceanographic parameters were also measured on sampling sites. Controlled tolerance experiment testing copper were performed on coral organism. Series of exposures at different range concentrations (0.025, 0.050, 0.075 and 0.100 mg L-1 Cu) were conducted for 96 h LC50. Results indicated that low variation existed among some oceanographic parameter in depth. Higher concentrations of Pb and Fe were detected in coral tissues. Short duration (24 h) laboratory assay demonstrated dramatic effects ( tissue bleaching and death) on coral at copper concentrations (0.1 mg L-1 Cu). The LC50-96 was determined to be 0.032 mg L-1 Cu (II). The present experimental results demonstrated that heavy metals can have deleterious effect on coral animal, at relatively low concentrations and for brief exposures.
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On metals in the aquarium and their sources.
http://reefkeeping.com/issues/2003-04/rhf/feature/

 

[jason2459]

FYI, that quote above is from Randy Holmes-Farley. For some reason it didn't copy that part it seems.

 

[Dan_P]

FYI, that quote above is from Randy Holmes-Farley. For some reason it didn't copy that part it seems.

Good stuff!

 

[Reefer40b]

This is some good stuff, good to see some more people responding to this!

 

[2smokes]

Randy Holmes-Farley retepy is for adding iron to the aquarium not for binding PO4.GFO works best in freshwater with a ph lower than 7.In saltwater with bigger than 7 ph, calcium is the best phosphate binder beating the GFO propertyes.Gfo was invented to treat freshwater but was later adopted in the saltwater aquarium hobby but isnt the best way to bond PO4.Kalk reacts with the phosphoric acid like this H3PO4 + Ca(OH)2 → CaHPO4 creating the floating detritus that we have in aquarium.When that detritus settles down and gets compacted(in nature) it becomes a stone ,mineral called monetite.Liquid GFO wont work because youl have to poison the aquarium with lots of iron to bond less PO4 than you could bond naturally by using kalk.

 

[dartier]

Randy Holmes-Farley retepy is for adding iron to the aquarium not for binding PO4.GFO works best in freshwater with a ph lower than 7.In saltwater with bigger than 7 ph, calcium is the best phosphate binder beating the GFO propertyes.Gfo was invented to treat freshwater but was later adopted in the saltwater aquarium hobby but isnt the best way to bond PO4.Kalk reacts with the phosphoric acid like this H3PO4 + Ca(OH)2 → CaHPO4 creating the floating detritus that we have in aquarium.When that detritus settles down and gets compacted(in nature) it becomes a stone ,mineral called monetite.Liquid GFO wont work because youl have to poison the aquarium with lots of iron to bond less PO4 than you could bond naturally by using kalk.

I get it, you like Kalk. You have made that clear in this thread and the one on DIY Coral Snow. However before you start making too many generalizations on the applications of iron solutions, some reefers with very, very successful techniques/tanks do use iron based solutions for phosphate control. Probably the best example is Glenn Fong's tank (http://www.reefcentral.com/forums/showthread.php?t=2395250).

At this point we are simply exploring the (possible) application of this new method of phosphate control and considering its method of working.

Dennis

 

[jason2459]

Randy Holmes-Farley retepy is for adding iron to the aquarium not for binding PO4.GFO works best in freshwater with a ph lower than 7.In saltwater with bigger than 7 ph, calcium is the best phosphate binder beating the GFO propertyes.Gfo was invented to treat freshwater but was later adopted in the saltwater aquarium hobby but isnt the best way to bond PO4.Kalk reacts with the phosphoric acid like this H3PO4 + Ca(OH)2 → CaHPO4 creating the floating detritus that we have in aquarium.When that detritus settles down and gets compacted(in nature) it becomes a stone ,mineral called monetite.Liquid GFO wont work because youl have to poison the aquarium with lots of iron to bond less PO4 than you could bond naturally by using kalk.

Randy was specifically replying to my question directly related to binding PO4 with iron citrate.

This is not the first time you've posted/ranted with out reason or research.

GlennF specifically doses iron citrate for the purpose of binding PO4 which is what the discussion between Randy and I was about. If I recall correctly GlennF has elevated his aquarium to .25ppm of iron after dosing. I can't link to Glennf's thread on another site to point to where he has said it. He may have on this site too as he posts here. Iron citrate could be an effective method. I would be hesitant to do so as I've posted why up earlier in this thread. People can very well disagree and still be respectful to each other. I believe GlennF to be a very successful reefkeeper.

I would love to see more documentation on testing the effectiveness of limewater dosing into an aquarium to reduce phosphates. I don't see it happening at an effective rate but I could be wrong.

If wanting to use some form of Ca then Calcium Carbonate seems to be a much safer method with out the risk of spiking alkalinity and pH.
http://reefkeeping.com/issues/2006-09/rhf/#10

And according to Randy in that article Craig Bingman failed to show appriciable reduction of PO4 with the use of limewater in an article Craig published in Aquarium Frontiers magazine.


I would also love to know where you can show that GFO is less effective at reducing PO4 then either CaOH or CaCO3?

 

[2smokes]

To dose iron for PO4 controll is risky .It isnt like the GFO wich doesnt leaks iron into the water.Iron in the natural seawater is verry low.Soo low that we dont have such performant tests to check the iron(see Randy Holmes Farley conclusion about this).Gfo is good at taking po4 out of the water but when the rock leaches PO4 it cant do nothing.You will get with cyano on rocks even if you use GFO.The only thing that ,,cements,, the po4 in the rocks is the calcium .I would post somme links to back my statements that calcium is better than GFO at higher ph of the water like saltwater is but my links are scientific studyes and in romanian language.If somme is interested ,could google to gather information about gfo and youl see it was invented for fresh water and that calcium beats iron oxide in high ph water. CaCO3 efectiveness is zero because that stuff isnt soluble in water,we allready beated this dead horse in the otther forum.Better you take the CaCO3,burn it, then soak it in water for a few days and you get with nice CaOH .

 

[jason2459]

At highly elevated levels I've use LaCl3. It's extremely effective at precipitating PO4. I have suggested that to many to get phosphates down to levels that GFO can keep up with. It also has its risks.

I also agree liquid iron dosing for the purpose of reducing PO4 is risky. Posted that already.

I agree calcium can bind phosphates but don't believe so as calcium hydroxide. Theory is there but hasn't been shown in practice. At least not to any level that is practical to use in an aquarium.

This leaves GFO as being an effective and relatively safe method at moderate levels of phosphates in a saltwater aquarium.

I personally have not needed a PO4 binding method once I used lanthanum chloride to bring down extremely high levels of phosphates to moderately high levels, used GFO to bring down to maintenance levels, and let my carbon dosing and algae harvesting to take over from there.

I would still be very interested in those links.

 

[bertoni]

GFO clearly works well in saltwater aquariums. It can reduce the phosphate level of a tank very rapidly.

I haven't seen any evidence that Kalk is useful in dropping the phosphate level of a tank. There certainly are lots of tanks that get Kalk added regularly that still require GFO to maintain a reasonable phosphate level. The equation you give is a bit off, but I think that that reaction can happen only at high pH levels, far too high for a running tank. Also, monetite is slightly soluble in water. I'm also not sure why you think it would form a floating precipitate. It should sink to the bottom, given its density.

 

[Buzz1329]

At highly elevated levels I've use LaCl3. It's extremely effective at precipitating PO4. I have suggested that to many to get phosphates down to levels that GFO can keep up with. It also has its risks.

I also agree liquid iron dosing is risky. Posted that already.

I agree calcium can bind phosphates but don't believe so as calcium hydroxide. Theory is there but hasn't been shown in practice. At least not to any level that is practical to use in an aquarium.

This leaves GFO as being an effective and relatively safe method at moderate levels of phosphates in a saltwater aquarium.

I personally have not needed a PO4 binding method once I used lanthanum chloride to bring down extremely high levels of phosphates to moderately high levels, used GFO to bring down to maintenance levels, and let my carbon dosing and algae harvesting to take over from there.

I would still be very interested in those links.

Thanks. I appreciate clear and logical summary of your posts in this thread.

Mike

 

[2smokes]

The links are scientific links in romanian language but im sure you could find them in english too if you google.My job is to test the water,air and soil ,then take actions to protect the enviroment, so i know what im talking .An easy experiment with GFO vs kalk vs the CaCO3 bonding PO4 abilityes would reveal the truth but i dont have time for this.The reason why PO4 is soo low on reefs in nature is because the there is a lot of disolved calcium in that area that binds the phosphate.There is no GFO reactor to keep the PO4 down in nature.Most beautifull sps aquarium i know doesnt even uses GFO, and has low PO4 ,i think mainly because of the Calcium and water changes.