Lanthanum - safe or not?

[Damien Buckley]

Wondering what your opinions are on the use of lanthanum for phosphate reduction?

There seems to be a lot of conjecture and opinions out there but so don’t see much real testing or evidence. I used it for 3 months and lost 3 clams that had been in the tank for a while. When discussing it elsewhere I’ve had all manner of comments from people using it and no issues to the same - loss of clams etc. I used an aquarium product but the way - not pool-type chemicals.

Triton list *any* amount of lanthanum as dangerous so it’s pretty clear what they think.

 

[EmdeReef]

Wondering what your opinions are on the use of lanthanum for phosphate reduction?

There seems to be a lot of conjecture and opinions out there but so don’t see much real testing or evidence. I used it for 3 months and lost 3 clams that had been in the tank for a while. When discussing it elsewhere I’ve had all manner of comments from people using it and no issues to the same - loss of clams etc. I used an aquarium product but the way - not pool-type chemicals.

Triton list *any* amount of lanthanum as dangerous so it’s pretty clear what they think.

It’s mostly safe but should be careful how you dose it as it can be too effective at stripping phosphates. Best practice appears to dilute with rodi and dose over time vs a concentrated quantity at once.

 

[Randy Holmes-Farley Verified Community Expert]

There's no actual safety "testing". There are a few reports of issues, and mostly people do not see a problem.

It isn't my preferred method, unless you are treating new rock before setting up the tank, but it is probably going to be fine if you use it.

The term dangerous from Triton may just be a translation issue for elevated levels. They say many things are dangerous without it seemingly being true.

Just be sure to not drop phosphate too low, which is more of a problem than elevated phosphate.

What is the level now?

 

[jsker]

I use lanthanum chloride to bring down my phosphates when the phosphate get higher than I like. I do use GFO to maintain my phosphates.

 

[Damien Buckley]

There's no actual safety "testing". There are a few reports of issues, and mostly people do not see a problem.

It isn't my preferred method, unless you are treating new rock before setting up the tank, but it is probably going to be fine if you use it.

The term dangerous from Triton may just be a translation issue for elevated levels. They say many things are dangerous without it seemingly being true.

Just be sure to not drop phosphate too low, which is more of a problem than elevated phosphate.

What is the level now?

I’m not using lanthanum anymore. I’m currently using GFO (Phosban). Phosphate was 0.05ppm yesterday which I’m happy with.

I used lanthanum (a ‘Phosphate Remover’ aquarium product) for just over 2 months mixed 50/50 with RO and was able to set the drip rate of 3-4ml per day (so 1-2ml actual product). At this rate the phosphate was testing 0.02 to 0.04 on average, occasionally dropping to zero, using a Hanna Phosphate Checker (not the Phosphorus ULR).

I was dosing it in 1ml doses into the downflow chamber in the hope that most was caught by the filter socks and then the skimmer chamber.

Before I started using it I had a 3-4” clam I’d had for over a year and a half and two newer 1-2” clams plus a large 6” squamosa. Within 2 months all 3 smaller clams were dead and I stopped using the lanthanum. The larger clam seemed relatively unaffected but since I stopped using lanthanum it has spread its mantle more and is open most of the time whereas it was closed a lot previously.

Nothing else in the tank appeared to be affected - I have a mixed reef with SPS, LPS, shrimp, snails, fish. Only the clams were affected…

I also noticed that my calcium levels went up. I’m not sure if this is because the lanthanum was pulling the calcium out of my rocks or just because the tanks uptake reduced. The calcium levels have normalised since I cut the dosing too.

Triton tests taken during the lanthanum use showed levels at 41ug/l, slightly high Iodine 193ug/l, moderate molybdenum 51ug/l and high silicates at 699ug/l. Everything else normal and in the green.

The latest test (after stopping lanthanum and running a Polyfilter for 2 months) have lanthanum at 3.3ug/l, low Iodine 19ug/l as Id stopped dosing it, molybdenum down to 31ug/l, silicates down to 216ug/l. Everything else normal.

I can’t attribute the clam deaths to the lanthanum definitively but I don’t have any other explanation and I’ve read of others losing clams while dosing lanthanum. I know my Iodine was a bit high but I don’t know if that would affect clams?

I did read this morning of an iron-based liquid product favoured by the DSR method which supposedly works like lanthanum but have to say after the clam deaths, I prefer the idea of an extractive media to a binding agent. It’s just harder to control…

 

[vanpire]

I hope this doesn’t happen to me but I have been dosing lanthanum chloride for about 1.5 months.

I have a large deresa and so far no observable effects.

I does mine into a 5 micron filter sock. Great for removing phosphates.

 

[Damien Buckley]

I hope this doesn’t happen to me but I have been dosing lanthanum chloride for about 1.5 months.

I have a large deresa and so far no observable effects.

I does mine into a 5 micron filter sock. Great for removing phosphates.

I use 225 micron Red Sea filter socks so perhaps you will have no issues. I didn’t see a lot of problem with my large squamosa but the small ones, gone. If your clam isn’t closing up I wouldn’t worry about it. I had a discussion with someone from a large aquarium company who stated that lanth-based phosphate removers leave a fine silt in the water column which is toxic to fish gills etc and possibly corals.

You must be swapping 5 micron socks out constantly?

 

[Sallstrom]

We use LaCl at work but very carefully. I know of a couple public aquariums that stopped using it because they think it killed fish at their aquariums(I think they say tangs are among the most sensitive).

I'm not a chemist so this might not be totally correct, please correct me if I'm wrong. Lanthanum Chloride might be dangerous if a fish(the gills) get exposed to "free" La that hasen't binded to a PO4 molecule. Therefore it is more safe to use LaCl when there is more PO4 compared to low PO4. And that is why dosing should be done a little at the time, not one big dose.

We have used LaCl for a couple of year at work. We buy powder from a chem company(Lanthanum(III) Chloride) and mix it with RO water and then dose with dosing pump at the intake to our sand pressure filters. We have also tried to dose directly to a skimmer in a cold water system.
We only dose LaCl when PO4 is higher than 0,1. If the PO4 is lower we use regular phosphate remover(GFO).
Our doses are very low, about 1-10 gram for aquariums with volume 5000-26000 litres. So what I have seen it's seems to be very effective.
We have never seen La in our ICP tests, and we haven't seen any harmed fish, clams or corals, so I guess we are on the safe side with our doses.

/ David

 

[vanpire]

I use 225 micron Red Sea filter socks so perhaps you will have no issues. I didn’t see a lot of problem with my large squamosa but the small ones, gone. If your clam isn’t closing up I wouldn’t worry about it. I had a discussion with someone from a large aquarium company who stated that lanth-based phosphate removers leave a fine silt in the water column which is toxic to fish gills etc and possibly corals.

You must be swapping 5 micron socks out constantly?

I only add the 5 micron filter sock when I dose. Yes, it does clog up in about a day and less when it is older even though I clean it

 

[JeannieS]

Where can I get a 5 micron filter sock?

 

[Cabinetman]

Everyone having issues it seams use higher micron filter socks. Those seeing problems are because the flocks are getting into their tanks. You gotta use 5 micron or lower socks! I actually only dose it to my sump. I plumbed in a fitting that hangs above my skimmer section that I can clamp a 5 micron sock too. This way it hangs above the water so I can tell when it’s plugged and plus I can pressurize it thus getting much more use out of it. I just dose the skimmer section and the water just recirculates in the sump until it runs clear. Only a few mins really. Then I open the valves to let it pump that water back to the tank and repeat after a bit if nessesary. I used to always see a bit of clowdy water getting into my tank before but not doing it this way. My nems used to close up but not this way. Faster and better and safer way in my experience..

 

[csb123]

I’ve been using it for over a year, and I haven’t noticed any bad effects. I have a maxima clam and she’s growing and happy. I dose it into my skimmer.

 

[inktomi]

I would second or third the statements about using a very fine filter sock and being extremely cautious. Tangs, particularly yellow tangs it seems, are extremely sensitive to getting it in their gills and once they do they don't do well, if they survive at all. The ultra fine particulate it makes seems to particularly affect them - so please do be careful!

It works extremely well though. A little goes a long way.

 

[Nate Chalk]

I would second or third the statements about using a very fine filter sock and being extremely cautious. Tangs, particularly yellow tangs it seems, are extremely sensitive to getting it in their gills and once they do they don't do well, if they survive at all. The ultra fine particulate it makes seems to particularly affect them - so please do be careful!

It works extremely well though. A little goes a long way.

I lost my tang last night to this very issue there needs to be more awareness out there for this so im relaying my story