calcium vs GFO binding phosphates

[jason2459]

Most sucessfull and most beautifull sps tank i know uses 2 part solution.2 part is the most comfortable way to keep Ca and alk stable because by using a kalk stirrer or a CO2 Calcium reactor you will still need to adjust especially alk from time to time.In an old aquarium with rocks that arent leaching phosphates it doent matter if you use kalkstirrer or CO2 reactor or 2 part ,the result will be the same .But in a new tank the higher ph of the kalk and the kalk itself will make a difference with kalk being the fastest to stop the phosphate leaching rocks from all the 3 different techniques to add Ca and alk.

And now you are talking about the best way to supplement Ca and Alkalinity. Plus what I posted about in Randy's article about pH benifits of limewater additions.


Let me remind you and keep on track here.

Just read the thread title you started.
Calcium vs. GFO binding phosphates

Your argument is that calcium hydroxide is more efficient then GFO and at least on par with LaCl3 at reducing phosphates in our saltwater aquariums.

Please, if you can back that up do so. If you can not then please say you can not. It really is that simple.

 

[bertoni]

We cant add much kalk at a time thats why it takes somme time until the stone is slowly cemented with calcium.

Adding Kalk slowly will not necessarily bind any interesting amount of phosphate at all. That's been demonstrated repeatedly by tanks that run with Kalk topoff. There's no proof that the equation you gave ever happens, although it might.

Its an approach that takes time but its the only way to stop a rock from leaching phosphates.

That's not true. There are a number of ways to solve this problem. Lanthanum chloride and GFO both have worked. There's generally more than one way to solve most practical problems.

GFO is fast because you can ad a big quantity at a time but it cant deposit on the rock surface so even if you use GFO and have O phosphates in the water you could still have algae or cyano on rocks because thoose are taking the phosphates directly from the substrate and not from the water.Craig Bingmann or any otther aquarist its sucessfull in bonding phosphates with calcium even from water changes but it takes time.To shorten that time you have to mantain higher a higher ph and stable because the calcium and phosphate compounds can disolve if the ph is swinging.I had no phosphate isuues in my aquarium while ive dosed kalk.After ive stopped the ph got low and then somme of the calcium and phosphates that were bonded together dissolved .The phosphates vere free and i had cyano and GHA that vere feeding from it.Personally i would use a low alkalinity salt so i could dose kalk continuously but with a kalk stirrer to mantain calcium,alk and ph stable.Dosing kalk through the top off works if you dont have big consumption of ca and alk.I still think that kalk is the best way better than the CO2 calcium reactor because the kalk gives you the ability to maintain a desirable higher ph easy.Addind 2 part solution is also good and basically every calcium and alk supplementation is good to bond the phosphates.

This is a bit unclear, but no calcium and alkalinity supplementation system can clear phosphate from a tank with a significant phosphate problem, otherwise we largely wouldn't have significant phosphate problems. Very few tanks go supplement-free.

 

[2smokes]

,,What you describe in your experience is what Randy commented on by using limewater you keep pH elevated enough to reduce the chance of the surface of the rocks from dissolving which would release phosphates. Nothing to do with calcium deposits on the rocks to protect it from PO4. And FYI your pH would have to be very low. ,,Randy Holmes Farley himself sayd that it unclear (even for him) how calcium bonds to phosphates.I prooved with the phosphate filter how powerfull calcium can be a phosphate binder.High pf doesnt prevent the rock from melting as you say but at higher ph the calcium reacts better,faster with the phosphates.Also ,by using top off water with kalk isnt the best way to experiment how calcium is bonding phosphates because you get too little kalk from the top off.A kalk stirre that doses kalk is much more powerfull and the results are visible ,clearer water,less impurities floating etc.But who uses a kalk stirrer ,doesnt use it to lower the phosphates even if its lowers them.Its mainly used to add calcium and alk and a higher ph but it also bond phosphates verry well.Lanthanum Chloride=poison and verry unnatural for a reef.The implication of this substance on the livestock is not known.And GFO works to take out the phosphates but only thoose from the water,it wont stop the rock from leaching,it wont cement the rock surface like calcium does.Gfo works faster than calcium because compared to calcium you can add a lot of GFO at once but in the long run calcium wins any battle with the GFO.I think that keeping a steady ph (and alk with it) its more beneficial than using GFO.

 

[jason2459]

Please quote correctly its hard to distinguish in a wall of text for people to understand.

It seems like you are now fabricating a discussion that was not previously there and back peddling at the same time while also rehashing examples to prove the point you're trying to back peddle from that do not prove that point.

And you're right with one thing there which is this argument, its very unclear how calcium hydroxide can efficiently bind PO4 in seawater which you believe it does.

 

[2smokes]

By keeping a steady ph and alk, you mantain the propper enviroment for the calcium to bond the phosphates onto rock surface.For the phosphates that are in the water(organic phosphates from feeding) its not necesarely to use GFO.Most ideally the organic phosphates from the water should be reduced by the biological filtration of the aquarium like bacteria and algae from an algae scrubber or a refugium.But even a powerfull biological filter like an algae scrubber cant do nothing to the phosphates that are leaching from the rocks in the display.Thoose only calcium can make them not to be a problem for the aquarist.

 

[jason2459]

Are you abandoning the stance that calcium hydroxide is more efficient then GFO at binding phosphates in seawater?

 

[jason2459]

So, to the only thing keeping me going is the idea that the theory is there which I agree with. Its the proof that is needed now to allow calcium hydroxide to be used to bind enough phosphates to at least be equal to GFO in effectiveness.

Thinking about that reactor theory I mentioned before. Multiple stages and closed loop with the system. Would have to be large or very slow but couldn't be to slow.

First stage would be a chamber of supersaturated limewater that water is mixed through. So, vinegar would be continuously injected into that chamber as well as lime.

Effluent would need to be filtered out of impurities as the precipitated metals would still be in suspension as well as hopefully CaHPo4 Some filtering mechanism for the next stage. 1 micron assuming since the precipitation caused by lanthanum chloride can be filtered out.

The alkalinity would be high? A stage of mixing with muriatic acid.

Then heavy aeration chamber before entering back to the aquarium.

 

[2smokes]

Are you abandoning the stance that calcium hydroxide is more efficient then GFO at binding phosphates in seawater?

No.Kalk is more efficient than GFO for manny reasons.It makes your water cristal clear instantly,it adds calcium and alk and increses ph making the perfect enviroment for the calcium to bond the phosphates faster.GFO is good because you can use a lot at a time unlike kalk but the GFO does nothing to the inorganic phosphates that are leaching from rocks.GFO highest efficiency is achieved at a lower ph than 7 while kalk beats the GFO at higher ph than 7.All seawater should be higher ph than 7 therefore kalk is better than GFO.GFO was made for use in fresh water because its better than kalk at lower ph than 7.

 

[jason2459]

Kalk will help purify the water it's mixed with. Not the water it's dosed into. That's what Randy refered to as self purifying because many elements will precipitate out and settle to the bottom which you would not want to dose.

I do like the ability to dose calcium and alkalinity in a fairly balanced approach easily. But didn't you just say 2 part was better?

GFO works perfectly well at the pH we keep our tanks.

Iron Oxide Hydroxide (GFO) Phosphate Binders - Randy Holmes-Farley
http://reefkeeping.com/issues/2004-11/rhf/index.htm

 

[tmz]

To iterate some of the more salient points:

Calcium from Calcium hydroxide or other compounds like calcium carbonate may bind some inorganic phosaphate but there is no evidence to support the notion that dosing kalkwasser actually does precipitate it though it seems plausible to think so .Experience dosing kalkwasser to reef tanks shows no such results . If any calcium phosphate precipitation is occurring it is de minimus IMOand IME.

There are limits to the amount of calcium chloride and carbonate and or calcium hydroxide that can be dosed while maintaining other critical parameters like pH,salinity ,alkalinity and calcium levels which makes many of the examples cited in support of calcium as a superior orthophpsaphate control for a reef tank a specious position.

 

[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.

This was my only post in this thread. Nowhere here did I attack your poor English skills. I did say on the other thread that you seemed uneducated, but that was about how you try to build arguments not language skills.

And yes, I do think it is ridiculous to talk about phosphate leaching from a rock made of calcium carbonate and then in the next sentence to say that only calcium could bind that back up. That's not a language or writing skills fail. That is a logic fail. If calcium was such a potent binder of phosphate then we wouldn't have any issue with it leaching out of the rocks.

 

[disc1]

I also never called you any sort of troll. I only pointed out the flaws in your argument. You seem to have partial information and are drawing intuitive conclusions based on it that are just plain wrong.

 

[jason2459]

I did allude to the possibility of trolling since there was no forward movement in the discussion. Only rehashing or side stepping of and with invalid points of which many were off the wall. This behavior spreads across many threads and subjects. I also apologized if I was wrong. I still feel unclear about it.

 

[disc1]

I did allude to the possibility of trolling since there was no forward movement in the discussion. Only rehashing or side stepping of and with invalid points of which many were off the wall. I also apologized if I was wrong. I still feel unclear about it.

And that's the problem I have with it. Instead of coming with numbers or in this case binding constants or solubility products, 2smokes just changed the argument. And quite often those arguments seem to not follow from one to another. Then, when actually called on any of them, he switches to ad hominem, "oh you're a big meanie what makes you think you know more than me" stuff. If he would make an actual scientific argument I'm sure it would've entertained better by the group.

 

[disc1]

Really the whole thing isn't worth arguing. It's a simple experiment. You need a phosphate checker, some Kalk, some gfo, and some water that's high in phosphate. Within a few hours this could be laid completely to rest.

 

[2smokes]

I also never called you any sort of troll. I only pointed out the flaws in your argument. You seem to have partial information and are drawing intuitive conclusions based on it that are just plain wrong.

Randy Holmes Farley comes with partial informations and intuitive conclusions too in his article about kalk.Im not as good chemist as him so forgive my ,,intuitive conclusion,,after i reread what i writed i think i gave the best explanations for the calcium binding phosphates ever to be written in this hobby.The bad tone ive used it isnt from my fault.

 

[tmz]

after i reread what i writed i think i gave the best explanations for the calcium binding phosphates ever to be written in this hobby.

I strongly disagree

 

[sde1500]

after i reread what i writed i think i gave the best explanations for the calcium binding phosphates ever to be written in this hobby.

Lol how humble of you.

 

[bertoni]

Randy Holmes Farley comes with partial informations and intuitive conclusions too in his article about kalk.Im not as good chemist as him so forgive my ,,intuitive conclusion,,

I don't think you understand his papers very well. You still ignore the reality that your theory doesn't work in actual tanks.

 

[2smokes]

Actually, we know calcium does NOT bind to phosphate freely in saltwater. Otherwise, phosphate always would be zero. Saltwater has a lot of calcium in it. Your example is polyphosphate, not phosphate, as well. We are concerned with phosphate (orthophosphate). That's what our test kits measure.

There are antiskale filters made from ortophosphates not only polyphosphates.