NP Bacto balance + Elimi-phos rapid combo

[KGV]

I have been a very happy user of NP bacto balance for half a year now. But as many have observed, while NO3 stays stable, PO4 still creeps up. I have an acro dominated tank where I like to keep PO4 around 0.05. I just quit using GFO because it pulls out too many trace elements and I want to start using Elimi-phos rapid (lanthanum) because that seems be binding PO4 more specifically .

However, Tropic Marin recommends switching to GFO or aluminum oxide-based products once PO4 is below 0.2-0.4 ppm. Why is Elimi-phos rapid not recommended for maintaining low ranges of PO4 @Hans-Werner @Lou Ekus? Is it not efficiently binding when PO4 is low?

Many thanks in advance!

 

[sixty_reefer]

I believe you answered your own question, lanthanum is not effective removing phosphate at low Po4 residual.

 

[KGV]

I believe you answered your own question, lanthanum is not effective removing phosphate at low Po4 residual.

Thanks @sixty_reefer. In that case, I think Tropic Marin should perhaps indicate that Lanthanum binding is non-linearly dependent on the PO4 levels and that dosing instructions only apply for PO4 levels above 0.2 PPM, for example. They sort of say that, but in a convoluted way.

 

[Randy Holmes-Farley]

I do not see that as the explanation as lanthanum can easily lower phosphate as low as you want.

I cannot say why other people claim what they claim, but lanthanum can easily drive phosphate too low, and also carries its own risks, which are two reasons to avoid it. If you prefer lanthanum, then keep using it carefully.

 

[Randy Holmes-Farley]

Thanks @sixty_reefer. In that case, I think Tropic Marin should perhaps indicate that Lanthanum binding is non-linearly dependent on the PO4 levels and that dosing instructions only apply for PO4 levels above 0.2 PPM, for example. They sort of say that, but in a convoluted way.

No, that's not the reason.

 

[KGV]

Thanks @Randy Holmes-Farley. Another explanation may be that free Lanthanum is toxic for gills and liver of the fish while bound Lanthanum is not. Hence that when the PO4 levels are low, it takes longer for Lanthanum to bind, increasing the risk of free Lanthanum meeting your fish and possibly other organisms.

On the side: This popular idea of Lanthanum flocculate "blocking" the fish gills don't make sense IMO. You can add many forms of small particulate matter to the fish tank and fish will be ok.

I am somewhat surprised because as a medical professional, Lanthanum for PO4 reduction in patients, is thought of as very safe.

 

[Randy Holmes-Farley]

I am somewhat surprised because as a medical professional, Lanthanum for PO4 reduction in patients, is thought of as very safe.

Yes, but mostly because it's poorly absorbed. Large amounts in the blood might be a different story. Two of my products (sevelamer carbonate and sevelamer hydrochloride) compete with lanthanum in that business.

 

[KGV]

Yes, but mostly because it's poorly absorbed. Large amounts in the blood might be a different story. Two of my products (sevelamer carbonate and sevelamer hydrochloride) compete with lanthanum in that business.

It didn't take long to find toxicological analyses of free Lanthanum on marine aquatic animals. https://core.ac.uk/download/pdf/82530733.pdf

It seems to me that you want to have this bound to PO4 as fast as possible and not have it linger around in it's free state for too long.

 

[Lou Ekus]

I will defer to @Hans-Werner on this one. He would be the explanation that I would trust. My understanding of the suggested application reduction is two fold. First, the Lanthanum chloride is a very aggressive approach to PO4 reduction and is needed if the concetration is extremely high. As far as I can see and have heard, the only danger in relation to gills and O2 assimilation in fish is in relation to yellow tangs very specifically. And that information is usually presented in somewhat anecdotal examples. Although those examples seem pretty valid.

 

[Lou Ekus]

Sorry, I hit the wrong key and there is more to that last post...That aggressive reduction of PO4 can also easily "overshoot" your desired decreased concentraion and result in a bottoming out of that PO4 that is not ndesired....The second eason for the suggestion, in my understanding, is that when using Lanthanum Chloride, all you are doing is causing a PO4 precipitate that is not benifiting your corals as much as the carbon dosing can. so switching backm to the ELIMI NP will also switch back to a more benificial situation in relation to coral health benefits....

 

[Lou Ekus]

that is my understaning of the reasoning. I will wait for @Hans-Werner confirmation of my thoughts, though.

 

[Randy Holmes-Farley]

It seems to me that you want to have this bound to PO4 as fast as possible and not have it linger around in it's free state for too long.

That's a reasonable hypothesis, but I'm not aware of any data supporting it in reef tanks. I've never made any claim whether the toxicity that folks see with tangs relates to free dissolved or particulate lanthanum materials. It could be either one. I've never seen any other toxicity reported by users unless they dropped phosphate very fast.

.FWIW, phosphate is not the only way it will precipitate. It will bind to calcium carbonate surfaces and may even precipitate as lanthanum carbonate.

 

[rishma]

I have been a very happy user of NP bacto balance for half a year now. But as many have observed, while NO3 stays stable, PO4 still creeps up. I have an acro dominated tank where I like to keep PO4 around 0.05. I just quit using GFO because it pulls out too many trace elements and I want to start using Elimi-phos rapid (lanthanum) because that seems be binding PO4 more specifically .

However, Tropic Marin recommends switching to GFO or aluminum oxide-based products once PO4 is below 0.2-0.4 ppm. Why is Elimi-phos rapid not recommended for maintaining low ranges of PO4 @Hans-Werner @Lou Ekus? Is it not efficiently binding when PO4 is low?

Many thanks in advance!

I know not the focus of your post, but I actually I observe the opposite with NP bacto balance. Phosphate stays pretty stable, Nitrate tends to drop toward zero. Interesting ….

 

[Hans-Werner]

that is my understaning of the reasoning. I will wait for @Hans-Werner confirmation of my thoughts, though.

Yes, the points already mentioned by @KGV and @Lou Ekus are correct and have prompted us to give a lower limit of phosphate concentrations on the package.

At lower phosphate concentrations the reactions between phosphate and lanthanum need more time and both remain longer in the water. Also using Elimi-Phos Longlife (GFO) at the lower concentrations is less aggressive and more controlled. It is a bit difficult for me to explain in English.