Lanthanum chloride

[pecan2phat]

So why does the LaCl need diluting?
I saw that some were diluting 5ml (1tsp) into 5gl of RO water to slowly drip over a course of a couple of hours.
Why can't you dose x-amount of undiluted LaCl at 1ml per hour using a medical doser instead of diluting the product?

TIA

 

[Elliott]

So why does the LaCl need diluting?
I saw that some were diluting 5ml (1tsp) into 5gl of RO water to slowly drip over a course of a couple of hours.
Why can't you dose x-amount of undiluted LaCl at 1ml per hour using a medical doser instead of diluting the product?

TIA

it takes so very little of LC to lower phosphate in a rather large volume of water, so diluting it is important to avoid lowering phosphate too much and too rapidly

also, you want to expose a high volume of tank water to LC, so diluting it makes this possible

 

[tent boy]

Not using the correct bags or not diluting the LaCl is asking for trouble. Just stick with the recommended steps and it works. Modifications could be disastrous for the fish.

 

[Dustin1300]

I've not dosed another time since last Saturday. Last time I diluted 5 mL LaCl3 in 1 L of RO/DI and definitely had cloudiness in the water. If phosphates are lower, does it make more sense to drop the LaCl3 dosage and further dilute it? Say 2 mL LaCl3 to 2 L of RO/DI?

 

[Scej12]

@Dustin; then All...

@Dustin; then All...

I would dilute your original dosage in any event to try to avoid the cloudy water. In terms of the exact concentration, I think that is just a matter of personal preference considered against how long of a period you take to administer your dosage. I personally have 150 mL of LaCl3 diluted in a 19L container, but this just drips in at about 1 -2 drops per minute now that the PO4 is at optimal levels... this container doesn't need refilling for about a month or longer.

And BTW, I don't use filter socks on this or any other system of mine for that matter... only 'cause I like to have the skimmer do the job of pulling out those precipitates.

Also, and by the way, I think the key to this process is removing the precipitated PO4 as soon as possible, which is why the 10 micron filter sock method works so great. I posted some picks of my DIY setup a number of weeks ago, and I believe what I'm finding suggests that the precipitated PO4 will at some point (probably as soon as the LaCl3 is exhausted) redissolve back into the water column in a manner similar to liverock leaching PO4 back into your system. If you remember the subject DIY I had all of the effluent pass through the CaCO3 reactor prior to reaching the skimmer... well, when the system was first initialized, the PO3 dropped in half relatively quickly (from 0.68ppm to 0.35ppm) within the first couple of weeks of moderate dosing. Well after those first two weeks my progress hit a wall... it seemed at first that if I cleaned out the three canisters, that the PO4 would drop a few parts, but would then climb back up after 3 or 4 days or so. I began to suspect that the precipitated PO4 is not making it past the CaCO3 reactor in order to be skimmed out by the large skimmer next in line.... in otherwords, I strongly believe the calcium reactor became a 'phosphate bank' - catching the precipitates that reacted past my last (carbon filled) canister via mechanical filtration, then redissolving same precipitates as soon as the LaCl3 lost its punch.

So last week I began removing the mechanical traps starting with the carbon in the third canister; since that didn't have the desired result, I just bypassed the calcium reactor, sending the treated water from the third (now empty canister) straight into the protein skimmer for precipitate removal.

If I'm correct, the PO4 will have dropped noticeably by my next visit scheduled for Sunday (only 4 days after bypassing the calcium reactor [mechanical trap!]), in which case I will conclude that this system works best when mechanically trapped PO4 can be removed right away. And I would also suggest that a calcium reactor is not an item that will be cleaned/serviced regular enough to be included in the exit route of any PO4 precipitation strategy. And for that matter, I don't think the sand filter route is ideal for the same reason - won't be cleaned enough to remove precipitated particles IMO although back-washing will remove some, but I don't think all.

Any how Folks - this account is more of a haunch at this moment (at least until I can confirm this Sunday), but I do hope this adds some relevant perspective to our collective understanding of this method...

Will Let y'all know how things test out on Sunday.

Regards,

Sheldon

 

[Scej12]

Bingo... (I mean 'Apparent Confirmation)

Bingo... (I mean 'Apparent Confirmation)

.... so I just arrived back from a day out with the fams; but before doing that, and even before doing a little shuttle running for my parents early this morning, I woke up extra early to visit my LaCl3 Reactor experiment. I know it's not Sunday as yet... in fact still less than 36 hours since by-passing the calcium reactor and routing the LaCl3 reactor effluent straight through to the skimmer; but I decided to have an early check just to be sure that I won't find a catastrophe early Sunday morning because I kept my highest dose rate going while cutting about 1/2 hour out of the time LaCl3 could potentially make it back into the sump and livestock system... So I snuck in an extra visit just to be safe.

Well as it turned out, my haunch seems to be firming up quite well. after 4 weeks stuck at 0.30 - 0.36ppm PO4 with the calcium reactor online and the system running for about 8 weeks all together; I removed the calcium reactor as described above; and bingo - less than 36 hours later the 'invisible wall' has been removed and the phosphate read (as of 07:00hrs this morning) 0.21ppm! That's a drop of 0.13ppm in about 32 hrs. At this rate, I suspect I'll be down to 0.10 by Sunday morning!!!

Sooo as it appears from this experiment, the Calcium reactor was acting as a "phosphate bank" in that it was catching precipitates while the LaCl feed was live; but re-releasing the same PO4 between LaCl3 doses; or at least [far enough down stream] when the system water no longer has strong enough traces of Lanthanum Chloride to keep the PO4 out of solution.

In conclusion; and just in case anyone is keeping track, the described experiments now pretty clearly suggest that the system of using LaCl3 to remove PO4 is only as good as how quickly you can remove the precipitates... therefore as has been discussed by most on this thread: filter socks work great because you basically have to remedy them as soon as they start to overflow; however, I'm also finding that in cases where it is not ideal to be managing filter socks; a direct feed into a skimmer (after some sort of reaction time allocation via some sort of pail or reactor/canister-bank) also works great IME since the skimmer does the same apparent job of removing out precipitated particles.... I've never gone the sand filter route, and quite frankly am not yet convinced that it will yield the same results as the previous two mentioned as I strongly suspect it will act to some extent as a PO4 Bank no matter how often you back-wash it simply because it appears to me that precipitates adhere to surfaces in areas of high flow (i.e. pumps; plumbing; reactor walls; media; etc.)

Anywho... hope this helps the avid DIYers out there & I'll be sure to report back any further confirmations following my Sunday morning visit. Until then...

Regards,

Sheldon

 

[Gary Majchrzak]

It all makes sense.
It sounds like you might be onto something but let's not forget the 'big boys' that use LaCl3 on public displays. In many (most?) cases they use SAND FILTERS to remove the precipitate. I don't know how quickly they change out a sand filter. It would be interesting to know.
Another thing: calcium reactors (alone) naturally release PO4 as media dissolves.
And the surface area of the reactor media (size of the aragonite)... I'm sure that it also has an impact on results. (Ditto with a mechanical sand filter.)


good stuff, Sheldon :thumbsup:

PS: feed the reactor effluent to your lit refugium / algae scrubbers

 

[Scej12]

thx Gary...

thx Gary...

It all makes sense.
It sounds like you might be onto something but let's not forget the 'big boys' that use LaCl3 on public displays. In many (most?) cases they use SAND FILTERS to remove the precipitate. I don't know how quickly they change out a sand filter. It would be interesting to know.
Another thing: calcium reactors (alone) naturally release PO4 as media dissolves.
And the surface area of the reactor media (size of the aragonite)... I'm sure that it also has an impact on results. (Ditto with a mechanical sand filter.)


good stuff, Sheldon :thumbsup:

PS: feed the reactor effluent to your lit refugium / algae scrubbers

Yeah - I've heard several mentions about the public aquariums using sand filters to remove the precipitates which is why I thought it was worth mentioning - might be an opportunity for them to investigate ways of improving the efficacy of this system...

Good point re the CaCO3 reactor. I was aware of this being stated, but have not been able to figure out exactly how much impact this will have... I was hoping that the LaCl3 could override any possible impacts as all other aspects remained the same. I happen to be using the coarse aragonite in these reactor chambers..

Okay - So call me an over-zealous kid in a candy store... I happen to have swung by my experiment once again this morning... only 25 hours after my last check-in (and it's still not yet Sunday!!). Well the PO4 has dropped another whopping 0.07ppm down to 0.14ppm - I think I'm on schedule to reach sub 0.10ppm by tomorrow morning..

This really is a revelation as I'm sitting here in front of the little white board in the filter room... it reads as follows:

"PO4 reactor initialized 2012-06-25; PO4 = 0.68ppm"

and above is my status tracking which reads:

"WEEK #8 - PO4=0.29"

I didn't update that for week 9 which would have read PO4 = 0.34ppm :hmm3:

So by tomorrow - I'll be noting:
"WEEK #10 - PO4=0.0(?)" :celeb1:

Regards All!

Sheldon

 

[Scej12]

BTW - I think I might just try that CaCO3 feed into the refugium suggestion next... I'll probably get around to cleaning and recharging it by tomorrow or Wed....

Thanks again.

SJ

 

[Gary Majchrzak]

jah! :thumbsup::thumbsup:

 

[Elliott]

The public aquarium here backwashes their sand filters daily

Sheldon, I think your conclusion makes sense, I ran LC into a pool DE filter for a 2 year period, I found that I had to backwash it frequently to keep phosphates down, so I instead set it up to only be "on line" when it was on, otherwise water was diverted and the filter was "off line". This worked best. The filter had it's own 30g reservoir that was fed with DT water only when the filter pump was on. However if I didn't backwash it in time my phosphates quickly went up, consistent with leaching P04 back from the filter as you suggested. I eventually abandoned the filter due to too much hassle.

I'm now running 2 ATS's and 3 good size protein skimmers that are working quite well. I clean the ATS's every two weeks and the skimmers have self cleaning heads so maintenance is a breeze.

You also bring up another point regarding the calcium reactor trapping P04 precipitates and becoming a p04 sink. While I believe this is true I also wonder if calcium reactors in general become nutrient sinks. They certainly act as a mechanical filter, does their low ph help "clean" them?

 

[Scej12]

I just find it amazing how many different angles yield impacts... Thanks for adding your account for validation.

So as it stands now in my view filter socks and skimmers all the way....

??? Calcium Reactor question...? Good one; guess we have to come up with an experiment to test that one as well in time... perhaps when we get bored.

Regards,

Sheldon

 

[Gary Majchrzak]

Sheldon- I love coupling my LaCl3 treatment with a wet skim water change.
You might want to consider it. It makes sense on many levels and IT WORKS GREAT.

 

[Scej12]

Hey Gary I'll be completely honest with you; the reason I never used filter socks on any of my Clients' systems is because I can't bring myself to clean them as often as required.... I'm waaaayy to lazy for that. So it sounds to me like wet skimming might also potentially relegate the use of filter socks as an emergency (quick impact) measure...

Regards,
SJ

 

[Scej12]

Oops!

 

[tent boy]

What has been everyone's experience with the longevity of the filter bags. I'm thinking that my bags have become " less effective" after several wash machine washes. Didn't catch much precipitate and water got cloudy. Didn't do that before. Bags getting old?

 

[Scej12]

No Change as of Sunday morning

No Change as of Sunday morning

Unfortunately I have not used filter bags/socks and so cannot comment on that one.

With regard to the experiment I've been documenting, I just got a chance to sit at my computer and should report that there was no further improvement after my Friday and Saturday visits. The PO4 remained at 0.14ppm... So I cleaned out the canisters and will see tomorrow if there's any further improvement. If there's none then I'll also clean out the polyethylene lines that carry the system water from the canisters back to the protein skimmer... you can actually see these PE lines turning from translucent to opague as precipitate lines their inner walls.

At this point I believe the stall in progress is a result of precipitated PO4 accumulating somewhere in the system and getting re-dissolved at a given mass of accumulation. Will report back Wednesday (tomorrow) when I have a chance to do another test. Hopefully the PO4 will be lower than 0.14ppm.

Regards,

Sheldon

 

[Dustin1300]

Sheldon,

I'd say keep at it and I'm very interested in what your investigations find. I think that with the right method and a few trials that this will work and just think, you were at .68 ppm at the start of this adventure. I started testing this method for the fact that I did not want to consider how much GFO I'd use once I get my 1000+ gallons going on my system. With the 300+ gallons of water volume I currently have I can use just about $.10 worth of LaCl and cut phosphates in half in a matter of a few hours.

I've been trying to consider several different methods with either reactors, large reservoirs, etc....And definitely think your onto something! Don't be discouraged:thumbsup:

Dustin

 

[Scej12]

Thanks Dustin, for your kind encouragement.

Keep in mind that I do already have a continuous run system that worked successfully, so I know that it's just a matter of working out the kinks in the system... I have no doubt that a continuous-run; system will work in the absence of filter socks. We just need to confirm the best way to remove PO4 precipitates within an optimal time-frame of the reaction... and eliminate areas for the PO4 to collect and re-release. I'm sure it'll work itself out.. in fact I'm looking forward to finding positive results by tomorrow night; if not after I change out the exit line (polyethylene).

Thanks again for your positive response. I'll keep you all posting as this process sees itself thru to positively stable results.

Regards,

Sheldon

 

[tmz]

Lanthaum phosphate (the precipitant) won't redissolve except in very acidic water over a long period of time .The solubility is very low. The La04P will not dissolve in a normal reef tank .

http://pubs.acs.org/doi/abs/10.1021/je00009a032

The danger with LaO4P ,lanthanum phosphate precipitants, is their effect on the respiratory apparatuses of the animals in the tank .Thus ,the need to filter very carefully and avoid cloudy water scenarios.