phosphate control, lanthanum

Charles Matthews here.

I had a discussion with Chuck Stottlemire recently in which I reviewed his experience with phosphate levels. Although phosphate has gone as high as 2ppm in his system, as he recalled without reviewing his notes, it appears sthat this level was only sustained for a week. Usually his phosphates run 0.2ppm. This is a bit of a mystery of me as he does not aggressively skim his tank and never uses binding agents of any sort.

With my previous husbandry techniques, I was feeding heavily and would notice sudden declines after peak administration of food. Phosphate was running well above 3ppm. I was rpredictably seeing declines, first in Pseudoplexaura, then in Scleronephthya, then finally in Dendronephthya. Perhaps the negative reaction after really heavy feeding had to do with release of soluble phosphate; it seemed to occur with oyster eggs and powdered food like Golden Pearls especially.

I have had some trouble with iron binding agents. There was considerable clumping with high food inputs.

The vodka method seemed limited by a flocculation effect that has been little discussed. After pushing vodka dosing and following nutrients, the water would become extremely clear, and at that time there was a negative reaction (whether to vodka toxicity or lack of food or whatever, I am not sure). I still dose vodka. However, because nitrate to some extent is turned to gas in anaerobic areas, one would expect phosphate accumulation anyway over time, since vodka exports nitrate and phosphate in rations similar to food inputs.

I recently started dosing lanthanum chloride in my system, but otherwise following the Stottlemire method. The reason I did this was because my Dendros were doing well, but the Scleronephthya and Pseudoplexaura were failing, and the Tubastrea aurea and micrantha were not growing much. Over two weeks I have brought the phosphate down from 2ppm to 0.2ppm. Nitrate declined at the same time (interesting) from 15ppm to 5ppm.

Everything is doing well- flame scallop, Dendros. The Scleronephthya are opening again (they're about halfway doing well, as opposed to obviously failing). I've done some testing on excess lanthanum (more than needed to remove orthophosphate) in small quantities of water. There was no effect on brine shrimp at 1/2 ml added to a half cup of brine shrimp. No effect on any organism (copepods, snails) with 2ml added to a 29 gallon on line in the system.

Lanthanum phosphate precipitate doesn't seem to be skimmed out to any extent, by my unofficial observations. I dose mine into a 120 gallon settling tank where it appears to go into the substrate; the water then flows to the NPS system.

There is a strong flocculation effect, which might interfere with feeding; I am looking into this. The water certainly can get very clear, and out of concern I dose something to keep a slight haze (RotiRich or activated yeast). Not sure whether this matters.

I am planning to write the second article on husbandry (I am planning a series). Most recently I was thinking of doing the article on lanthanum in controlling phosphate in NPS systems. I know that long term exsperience here is limited; another controversy is whether higher phosphate levels are problematic for NPS at all (I think it is).

The thoughts of the NPS community are very much appreciated.
 
No brilliant thoughts, but would like to read some elaboration on your lanthanum dosing--

lanthanum chloride?
commerciallyavailable aquarium "additive" or from pool supply
how are you dosing?

Thanks
John
 
I have always found that phosphate was tricky to reliably test. I have had frustrating results with most kits always testing zero on phosphates (mixed sps reef). This was with salifert and AP (lowest reading 0.03ppm). The frustrating part is I have had some consistent nuissance algae growth but with seemingly zero phosphate? :confused:

I then tried the higher end tests. I borrowed a photometer and got phosphate readings at 0.02ppm and 0.15ppm with a d-d merck test kit. I would guess that in more heavily fed systems that phosphate levels would be easier to test. That is assuming that phoshphates are normally going to be higher in an NPS reef tank (very, very heavily fed) vs. for instance an SPS reef tank (mediium-heavy fed).

All the testing I do is based on this <0.03ppm threshold for phosphate (for your average reef tank). What is the threshold for an NPS tank? Can it be a bit higher since a mostly NPS tank will have low lighting and less algae fuel in the form of light?

0.05- 0.1ppm max phosphate for NPS tanks? 0.5ppm? :mixed:

So assume we can reliably test for phosphate (high end test) and we have a target of ~ 0.1ppm. With NPS tanks running/peaking at 2ppm PO4 and maybe averaging a low of 0.2ppm then we may need to be aggressive with phosphate control. For PO4 control we have your GFO (granular ferric oxide) or Phosban, Phoslock etc. Then we have your Aluminum sulfate like Phosguard. These are both used in some sort of flow through media reactor. The only liquid phosphate remover I know is Phosbuster Pro.

With continuous feeding on NPS tanks it may be necessary to combine phoshphate removal methods to control the excess phosphates.

Can lanthanum chloride be used along with granular ferric oxide and/or aluminum sulfate?
 
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Re: phosphate control, lanthanum

<a href=showthread.php?s=&postid=12205028#post12205028 target=_blank>Originally posted</a> by charles matthews
Charles Matthews here.

I recently started dosing lanthanum chloride in my system, but otherwise following the Stottlemire method. The reason I did this was because my Dendros were doing well, but the Scleronephthya and Pseudoplexaura were failing, and the Tubastrea aurea and micrantha were not growing much. Over two weeks I have brought the phosphate down from 2ppm to 0.2ppm. Nitrate declined at the same time (interesting) from 15ppm to 5ppm.

I am planning to write the second article on husbandry (I am planning a series). Most recently I was thinking of doing the article on lanthanum in controlling phosphate in NPS systems. I know that long term exsperience here is limited; another controversy is whether higher phosphate levels are problematic for NPS at all (I think it is).

I found this interesting study involving lanthanum chloride use vs. alum for phosphate removal (in lakes). It discusses effect of pH, DOC on the P adsorption as well as some discussions about the resulting floc. I thought you might find it interesting. :D

On another note...I thought you had mentioned in the original dendro thread that the next article was going to be on scaling Chuck's system and keeping these corals in smaller systems?

Perhapys general guidelines or even an NPS minimum system requirements would be good to establish? Maybe your NPS article series could cover the major areas of concern i.e. NPS Reef Aquarium Nutrient Control article would include the information about lanthanum for phosphate removal.

IMHO :) :reading:

charles matthews,
I want to take a moment to express my sincere appreciation for all your efforts and tenacity with your research and sharing of information/ideas regarding Dendro/Sclero husbandry. Thank you. :rollface:
 
Thanks everyone for your thoughtfulness and help!

I've been working with SeaKlear, a lanthanum chloride product from the pool industry. It claims "removes 3000 ppb per 20,000 gallons of water". I found it by searching under the chemical name.

Since I started with 3PPM or so, this should have been gracious plenty. However, I've used about 1/4 of the bottle (enough for five thousand gallons) and still have perceptible slight color on the Salifert test kit (about 0.02 ppm, I haven't used a double reagent test). I presume there are multiple pools of phosphate species present that continue to equilibrate with orthhophosphate. There's a lot of phosphate in this system in various forms! (Total system is now about 500 gallons).

I'm having some recovery in my Scleros; the Dendros look OK. Still. things haven't really taken off. Nitrates are 2ppm or so now. Interestingly, the Chaeto and other macroalgae in one of the refugiums are doing much better and appear to have been phosphate inhibited (this has been reported before). I'm still dosing about 2-4ml/day. I have put it into the skimmer, but currently just dosing it into a large refugium which has a bead filter on it.

Regarding the article, I'm still getting more experience with lanthanum. I've used every other type of phosphate remover. There's a number of articles I want to write when time is ripe- 1) Probably an article on the syringe pump long term use, combined with remarks about phosphate removel and lanthanum if appropriate 2) an article about the rotifer drip system I was running for awhile (this eventually put too much phosphate into the main system and I may return to this if lanthanum works long term) 3) small NPS systems. 4) Fragging Dendronepthya. But, as Gauss would say, they are not ripe yet.

I really admire this group- keep up the great work!

Charles
 
Any update, mr Matthews?

Undiserable efects (chemical or biological)?
confirmation to reduction no3 by lanthanum?
aquarium evolution?
Thanks
 
Hello everyone

I have had some negative reactions in the Dendros but not so much the Scleros as the phosphate level came down from 3PPM to undetectable over about ten days. It seemed that things were responding positively as the level dropped, then suddenly negatively. Whether this was from too rapid reduction in phosphate (but why would that be?), a reaction to the lanthanum reaction products (but many have used this without problems) or, more likely, unreacted lanthanum dosed in excess of phosphate. Perhaps, also, I wonder if the phosphate test kit is accurate with lanthanum phosphate precipitate in the water.

The reason I am hesitant to use GFO is because it binds silicate as well as phosphate, and I dose silicate to NSW levels to encourage diatom and microorganism diversity.

In any event, damn if I know how Chuck keeps his phosphate so low (0.2ppm for the majority of the time) and whether it matters.

I'm back to trying GFO and still dosing silica.
 
Quick note- GFO is working fine, have left out lanthanum as tricky to regulate and raising too many questions for work with these organisms (they're complicated enough already!).

Have also stopped doosing silica- surprise, this led to a chronic increase in alkalinity I should have been testing for. The mechanism is
similar to the increase in alksalinity when dosing nitrate- sodium ilicate restores alkalinity with the charge is neutralized. After correction of severe resulting calcium deficit (DKH 27, 280 ppm! gradually over years, not looked at) all organisms doing much better.
 
Quick note- GFO is working fine, have left out lanthanum as tricky to regulate and raising too many questions for work with these organisms (they're complicated enough already!).

Have also stopped doosing silica- surprise, this led to a chronic increase in alkalinity I should have been testing for. The mechanism is
similar to the increase in alksalinity when dosing nitrate- sodium ilicate restores alkalinity with the charge is neutralized. After correction of severe resulting calcium deficit (DKH 27, 280 ppm! gradually over years, not looked at) all organisms doing much better.
 
Good stuff here guys! Very interesting reading. How about growing hair algae in a well lit fuge to acheave the same result of nutrient export? if too much NO3 is removed per too litle phosphate, why not dose it to acheave the proper ratio. I know it looks conterintuitive, but... what do u think? why not turn lemons (nusance algae in photosinthetic system) in to lemonade (food sorce 4 pods and P+NO3 removal agent)?
 
Been there, done that! I have used both a large algae scrubber (EcoWheel) and a macroalgae refurium, as well as fibrous pads as algae scrubber/plankton generators. I worked with dosing nitrate as per plant tanks in all these conditions. It does work, but...

In the end, GFO was much more controllable. Vodka also had problems with varying the particulates in the water (the sticky biofilms seemed to just suck up the phytoplankton). Remember, also, that nitrate comes with an ion. Interestingly, nitrate also raises alkalinity and could imbalance your calcium/alk ratio, and has to be compensated for. Over time, it's meaningful.

I like GFO with miracle mud denitrification. I turned my skimmer into a phosphate reactor and turned off the air. Adding phytoplankton by syringe pump adds plenty of carbon to the system
and polyp extension in everything is greatly improved, especially in Nephthyigorgia.
 
I have been reading with interest about the various methods of phosphate control, and wanted an opinion on an idea I've had using lanthanum chloride. It seemed to me the basic problem experienced was with the addition of lanthanum directly into the display tank or sump. The result was the sometimes irritiation of the livestock and lack of a method to effectively remove the precipitated flocculate.
My present setup has the sump in the basement. I have a 75gal tank that I was thinking of connecting to the sump with valves so that the inflow and outflow could be stopped , effectively isolating the tank from the rest of the system. Once this is done, the lanthanum would be added and allowed to do it's thing. Then I could either allow the flocculate to settle, or I could actively filter it out using my diatom filter. Once comlpleted, the tank is reconnected to the system. I also thought I could place a skimmer in this tank, which might also remove the flocculate. The end result would be 75gal of phosphate free (and lanthanum free)water returned to the system.
A variant of this scenario would be to have a skimmer or filter in the tank and to keep a continuous but very slow flow with the sytem using a surface overflow. Small amounts of lanthanum could be added on a regular basis and hopefully the flocculate would settle and be removed, whereas the clean water at the surface would return to the system. I thought I would throw this out here to see what people think, and that someone might see a problem I have missed before I start moving stuff around in the basement to try this out.
 
I'm begining small dosings of lanthanum chloride in my 150 gal SPS dominant reef. So far so good, I just drip 0,5 ml in my skimmer very slowly and collect half a cup of brown foam some minutes later (hope this is PO4-lanthanum flocculate).
 
I'm begining small dosings of lanthanum chloride in my 150 gal SPS dominant reef. So far so good, I just drip 0,5 ml in my skimmer very slowly and collect half a cup of brown foam some minutes later (hope this is PO4-lanthanum flocculate).

Hows is your tank now after 5 years? Is everything fine with Lanthum using?
 
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