calcium vs GFO binding phosphates

[2smokes]

I open this thread to talk about the abilityes of calcium to bond on to phosphates.Ive read once that Ferrous oxide works good but in fresh water with a ph smaller than 7 and that calcium works just as good at bonding phosphates but in water with ph bigger than 7(like the saltwater is).Somme sayd there is no proof that calcium bonds to fosfates efficiently.I think its wrong and i also think that in nature on reefs the calcium is the ones that bonds the phosphate not the GFO(wich is plain rust ,ferrous oxide).I dont say that GFO dont work to bond phosphates ,my goal is to demonstrate that calcium is better.So if you have an aquarium and you use GFO then add dry rock.That rock will start to leak phosphates and it will get covered in cyano no matter you have no phosphates in the water column because you use GFO.Only calcium can resolve the stone leaking phosphates problem.Calcium could come from the salt ,from water changes ,from adding kalk or running a calcium reactor.It also doesnt matter if the rock was soaked in acid or chlorine or that was baked(dont bake the stone too much because you will turn it into kalk ).It doesnt matter because thoose organics that the stone is leaking are inorganic phosphates and embeded in the rock.So the proof that calcium binds extremely well to phophates is this :best antikalk(descaler) that is in use for home and industrial purposes is the polyphosphate filter.Calcium bonds at an extremely high rate to these phosphates.This is whats happen in nature as well where theres no GFO reactor,calcium bonds the phosphates and ,,cement,, them.The polyphosphate filter is not for aquarium use but ive post it as an example on how calcium bonds to phosphates verry efficient.

On a side note ,somme people reccomend using CaCO3 to bind phosphated but thats not soluble in water.Adding powder sand to the aquarium wont bind the phosphates because the calcium is too stable as CaCO3 and will not break in to form otther chemical compounds.Kalk reacts with phosphoric acid creating a sediment mineral called monetite .This is the reaction . H3PO4 + Ca(OH)2 → CaHPO4

 

[bertoni]

You keep switching threads, so it's hard to have a discussion. I think I answered your points in other posts. I still don't see why you think calcium carbonate is better than GFO. The opposite seems true in practice. Nobody denies that calcium carbonate will bind some GFO. We see that all the time in new tanks with contaminated live rock that leaches phosphate.

 

[2smokes]

I made this thread so that we dont hijack the otther thread about liquid GFO idea.Here i posted the proof on how the calcium bonds to phosphates and at what rate by using the polyphosphate filter example.Its not a coincidence that the best antikalk filter in the world works with phosphates.Just people in the hobby arent too aware of this mechanism in wich calcium bonds the phosphates and how efficient it is.

 

[jason2459]

To late for the hijacking. We've already gone round and round getting no where.

1. You propose Calcium Hydroxide is superior to GFO
2. You have shown no evidence of that being practical in our saltwater aquariums

I agree calcium can bind phosphates in equilibrium with the seawater around it.

I've posted numerous times back and forth and provided many links.

None showed limewater as being able to effectively maintain lowered PO4 in our tanks. The theory is there. But as noted in another thread tests were done by Craig Bingman and results of testing limewater for that purpose were negative.

 

[jason2459]

So, to recap then

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

Originally Posted by Randy Holmes-Farley
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/

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?

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.

You must also make sure the tests apply to aquarium use. If limewater is an effective method and more so than GFO it must be at very unsafe levels for an aquarium. I do not know or have not seen any practical tests to show calcium hydroxide working to bind PO4. Theory is there.

So, I would love to see those links even if in another language and even if not practical for an aquarium. Formulas are universal and google can translate the rest well enough.

I have suffered from leaching PO4 from pukani dry rock when that product was first introduced and before it became common knowledge it leached PO4 like crazy.

If I were to do it again I would soak in bleach to help dissolve organics on it. Rinse, power wash and scrub , and rinse again. Then soak in a muriatic acid bath to strip that outer layer to help reduce the leaching PO4.

As it was I already posted the main method that worked best IMO. LaCL3 to GFO to Carbon dosing and algae harvesting.

The organics on the rock can release nutrients. The bleach will help break those down. The HCL bath will help strip the outer layers with bound PO4.

Lanthanum Chloride does have its risks but can be dosed safely with precautions. However, some dose with impunity and have had no issues, Melev.

LaCL3 safety concerns
http://www.reefcentral.com/forums/showthread.php?t=2544400





Where are you getting your information from? It seems very misguided in your posts. Or I'm curious what your motives are.

Still looking for practical testing for aquarium use of limewater to bind phosphates and how it's done.

GFO can exhaust in hours based on how much phosphates are in the water column. GFO can strip PO4 to stressful levels to corals. GFO has shown to be very effective in seawater.

LaCL3 is just as effective in our aquariums as it is in pools and can be to effective.

As Bertoni already stated this is not applicable to our reeftanks. And CaCO3's capabilities I did not question. Its calcium hydroxide I have issues with and would be very interested in how it could be applied to our tanks for PO4 reduction.

However, their mention of Renagel stood out as it is a product invented by Randy.

But we have yet to see a practical way to implement what you are promoting or backing up some of the things you are stating. Especially in regard to the usage of calcium hydroxide. And I wasn't referring to pushing a product as a motivation.

None of that has been shown to be true in regards to kalk binding any significant amounts of phosphates in a saltwater tank.

Yes, people have squirted in small amounts of kalk paste into aiptasia but people have damaged surrounding organisms but I'm not saying it will happen. I used kalk in the past like this as well and I have seen pH increases from it. It's very easy to test for and see since I have and had at the time continuous pH monitoring and logging.

I have used limewater to supplement Ca and alkalinity since around 2009. Never has it helped my PO4 levels or anyone else that I know of. If it required more there would be alkalinity and pH level issues. As saturated limewater you would have salinity issues.

I simply do not see your claims as accurate without some evidence. All evidence so far disagrees with your stance. Again, if I'm wrong I would really love to know how.

Nice article thanks. The pH binding rose above a pH of 9 shifting towards the calcium ions in the clay.

But the contention isn't the fact that PO4 will bind with Ca. That we know and experience with our rocks as the PO4 levels in the water drops the phosphates leach back out raising the waters PO4 levels again until there is equilibrium. This can go back and forth.

The issue comes in the form of Calcium Hydroxide and utilizing in our tanks as a means of PO4 reduction.

That is interesting the shifts in pH they studied.

Or it's the precipitated CaCO3 at the site of dosing CaOH that phosphates are binding too which the local dosing site will have much higher pH levels with limewater having a pH around 12. I can see that happening. But not at a very high level to be helpful.

My site of dosing has a nice build up of calcium. It would be interesting to see how much PO4 is there.

I'm not sure I understand the conclusion of your post between the opening and the ending.

I don't think anyone has proposed that this is a method to supplement Ca. Only that it may be useful as a flocculant to help skimming or other types of mechanical filtration.

Read the post you quoted would be a good idea. No mention of better or worse was made and stated what you are arguing that CaCO3 is not limewater. Maybe you quoted the wrong post?

There's some evidence that dosing lime may bind phosphates but not a significant amount. At least it has not been shown in practice afaik.

Under: "What Else Does Limewater Do In An Aquarium? Reduce Phosphate"
http://reefkeeping.com/issues/2005-01/rhf/index.php#15


There are some reasons to believe CaCO3 could help remove some metals and that PO4 could bind to it as well then get filtered out.

Under: "export of metals"
http://reefkeeping.com/issues/2003-04/rhf/feature/

 

[jason2459]

If you're going to use this thread then please do so.


Another post of skepticism.

Not hard to believe that phosphates can bind to Ca. We believe it quite well and have stated so several times. However, using limewater to do this has a basis in theory but not applicable in practice.

If someone could somehow make this work I would love to see it. A reactor of some kind somehow. Not a kalk reactor as that's shown to not be effective at all in reducing and/or maintaining PO4.

I also see no reason to believe GFO is not effective in our saltwater aquariums. It has been shown time and time again to be very effective at reducing PO4. I don't know how someone can say it is not effective in seawater.

 

[2smokes]

Jason,thoose tests were made by using kalkwater.Its still efective at bonding phosphates but i was talking by using a kalk stirrer with more kalk than what kalkwasser can provide.If you use kalkstirrer then you will be dosing a lot of kalk and the result would be easy to see with the naked eye to even the most novice aquarist.Instead of using LaCl wich is unnatural and becomes reef safe only after its eliminated from the system(wich i think is a hard thing to do and you would have to take all the detritus thats made of LaCl and phosphates) why not using a cheap,safe alternative like calcium ?Calcium is just as good as LaCl but isnt toxic.From what ive read in your link,the guy that used LaCL itself sayd that its dangerous and becomes reef safe only after it gets out of the system.How you will take the poisoned detritus from the system ?

 

[jason2459]

Jason,thoose tests were made by using kalkwater.Its still efective at bonding phosphates but i was talking by using a kalk stirrer with more kalk than what kalkwasser can provide.If you use kalkstirrer then you will be dosing a lot of kalk and the result would be easy to see with the naked eye to even the most novice aquarist.Instead of using LaCl wich is unnatural and becomes reef safe only after its eliminated from the system(wich i think is a hard thing to do and you would have to take all the detritus thats made of LaCl and phosphates) why not using a cheap,safe alternative like calcium ?Calcium is just as good as LaCl but isnt toxic.From what ive read in your link,the guy that used LaCL itself sayd that its dangerous and becomes reef safe only after it gets out of the system.How you will take the poisoned detritus from the system ?

Please, provide data backing up Ca is as good as LaCL3. Lanthanum Chloride is extremely effective and dangerously so. I never stated it doesn't have risk. It does for anyone reading this. I provided a link above where I questioned it's safety.

Limewater will help precipitate out many things which is why you might find the water running through the reactor is very clear but freshwater should be fairly clear in the first place that is running through the kalk in a kalk reactor.

How do you propose a kalk reactor will utilize more kalk then what can be saturated in fresh water? It just came up on another forum that someone tested the output of their kalk reactor and was surprised at unsaturated the limewater was exiting the reactor. Any kalk not dissolved will settle back down waiting to be stirred back up again. (refer to Randy's article in what your grandmother never told you about lime. linked above. Edit: here http://reefkeeping.com/issues/2005-01/rhf/index.php )

In a still water reservoir one could add some acetic acid to increase the saturation level of kalk but even that has shown to not be effective at lowering or maintaining PO4 by itself. (Randy did this for a while yet still used GFO along with his algae harvesting and carbon dosing to lower and maintain PO4 levels)

Limewater runs the risk of increasing alk to much and/or pH. If trying to dose limewater beyond evaporation rates that risk becomes greater along with salinity level issues. (repeating myself again)

 

[jason2459]

I just feel like this is trolling at this point and I questioned that earlier as well when referring to motives.

If a limewater reactor (not a kalk stirrer) or some other way to be able to utilize calcium hydroxide in a saltwater aquarium with out risk to reduce PO4 levels better then GFO or LaCL3 or at all can be shown and done in practice please let me know. I would love to be wrong and would try it myself.

 

[2smokes]

You could look into the medical industry to see that CaCl is an equal alternative to LaCL in treating people.Thats why i sayd theyr equal just that calcium isnt a poison for a reef tank like LaCL is.I apologise if i made you think this is a trolling thread and il stop the discussion here.We come on the aquariums forum to get informations and to have a good time not to fight with arguments.

 

[jason2459]

You could look into the medical industry to see that CaCl is an equal alternative to LaCL in treating people.Thats why i sayd theyr equal just that calcium isnt a poison for a reef tank like LaCL is.I apologise if i made you think this is a trolling thread and il stop the discussion here.We come on the aquariums forum to get informations and to have a good time not to fight with arguments.

Discussions are fine but I'm, possibly others, are still waiting for results applicable to our saltwater aquariums and we just keep going in circles repeating ourselves.

And I do apologies if that previous post came off as harsh.

 

[bertoni]

You could look into the medical industry to see that CaCl is an equal alternative to LaCL in treating people.

We're not treating people.

 

[2smokes]

We are not treating people indeed but the chemical propertyes of the substances remain unchanged.It was just an example just like the example with the polyphosphate filter that attracts all the calcium in the water for dedurisation.We dont use polyphosphates filter in the aquarium eyther ,but is a good example to understand the chemistry behind the phosphates and calcium.As for Jason,i didnt feel offended at all and i would made the kalk experiment by myself and post it here .Thing is i cant test it in the future because my new aquarium ,the ,, nuclear winter,, will not have phosphate issues.Il not keep corals in it and not even cyano wont be a problem because it will be an all time dark aquarium where not even cyano cant grow.I dont need a kalk stirrer for my aquarium or to keep phosphates in control so i cant do the test.The small reef i had ive donated and the plans for a new sps tank ive stopped in favor for the cold water, pelagic aquarium that i build.

 

[jason2459]

Actually in seawater there are many competing ions that can change how many things react compared to say freshwater.

 

[bertoni]

When we treat a person using lanthanum phosphate, they ingest the drug. Our animals aren't ingesting the lanthanum phosphate, not any any significant rate, so the comparison is inaccurate, in my opinion.

 

[2smokes]

No need to dose strange chemicals for a reef like LaCl.Kalk does the same thing and its used for same purpose as LaCl.

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

 

[jason2459]

No need to dose strange chemicals for a reef like LaCl.Kalk does the same thing and its used for same purpose as LaCl.

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

1. I see nothing there to support your claims.

2. You said Wiki is not a good source

 

[bertoni]

I agree that there's nothing to support his claims. People dose Kalk regularly into aquariums and still have phosphate problems.

 

[disc1]

Just read the first post. Let me see if I understand what he is saying. So the rocks which are made of calcium carbonate can't hold the phosphate and it leaches into the water. And his assertion is that the best thing to bind the phosphate that the calcium in the rock couldn't bind is calcium? Since calcium can't bind the phosphate the best thing to bind phosphate is calcium? That's what he's trying to say? When you parse it out like that you can see how ridiculous it sounds without knowing any chemistry.

 

[jason2459]

Yes, it's all quite silly and has been difficult to keep up with the conversation as it splits apart here and there in multiple threads. I keep trying to keep on target with the initial claim.

Which is: Calcium Hydroxide is superior to GFO in binding phosphates in our saltwater aquariums.


Multiple other points keep coming up. Like the most recent is Ca(OH)2 is just as efficient and safer then LaCl3 to reduce phosphates.