Lanthanum chloride

Gary, the 0.00 i got was before dripping the LC. Sorry for not being clear. Phosphate reading showed around 0.13 and 0.19 in the last few weeks. Sometimes I get 0.00 which leads me to believe that the phosphates are being consumed by algae. Yesterday before beginning the LC dosing, I tested and it showed 0.00. Now I don't have a reliable way to test for phosphates.

Should I go ahead and try another round of LC dosing, this time may be 5 ml per 1000 ml?

LC seems to become ineffective at lowering phosphate readings at around 1.4.
I would suggest that it is not the algae that is lowering your phosphate, but testing issues. Have you run multiple tests on the same water sample?
 
a week ago, it read 0.15 and yesterday it read 0.00 using hanna phosphate checker. I know phosphate is present due to enormous hairy algae and other types of algae.

I find I get different readings with my checker. If I take a couple and they are close, I go with them,...but sometimes they are way out of whack, and I blame it mostly on their reagent packaging. Some packs the power looks like a correct amount, other times seems like the packet got shorted. I wish they would turn it into a liquid forum, so you could count the drops.---Rick
 
Ok, i just tested the phosphates and it showed 0.04. I retested the sample one more time and still got 0.04. Which I think is a good news?

Seems to be!

So to recap, I got 0.00 phosphates in my initial testing presumably because of the presence of algae. I did a 2.5/1000 ratio of LC dosing and now I am getting 0.04 of phosphates. Which means to me that the LC dosing worked. How long does it take for the algae to die off after the LC treatment?

Maybe - but LC shouldn't be getting phosphate to be that low. Some reports show that efficacy of binding begins to drop off at .24 and several Public Aquariums find that levels below .14 are not achievable with LC.

The algae isn't necessarily getting its nutrients from the water column, and if your phosphate levels are bouncy, they may jump up soon. There are reports of phosphate levels bouncing back after significant drops due to LC dosing.
 
I use LaCl3 to control PO4 in order to grow stony corals as calcification is inhibited in the presence of high phosphates.

This is the common wisdom, but it may not be supported. From an upcoming article by me and Chris Jury:

"Two other recent studies have really begun to blow the lid off of what we thought we knew about the effects of elevated phosphate on corals. Godinot et al. (2011) examined the effects of phosphate concentration (0.00, 0.05, and 0.25 ppm) on growth and various physiological responses of the coral Stylophora pistillata. Similarly, Dunn et al. (2012) examined the effects of phosphate enrichment (0.09, 0.2, and 0.5 ppm) on the coral Acropora muricata. Both of these studies were performed in aquaria where at least some of the negative indirect effects of nutrient enrichment which can occur on a real coral reef, such as algal overgrowth, could be minimized. Surprisingly, in both studies the corals grew fastest at the highest phosphate concentrations tested (0.25 and 0.5 ppm, respectively). In fact, the rate of coral growth for both species increased linearly with the phosphate concentration. At least for A. muricata, skeletal density was also lowest for the rapidly-growing corals in the high phosphate concentration, though reduced skeletal density during periods of rapid growth is not necessarily unusual for corals. Hence, these corals were growing fastest and appeared to be "œhappier" at phosphate concentrations on the order of 5-10x greater than the commonly recommended upper limit for reef tanks, or about 10-50x the phosphate concentration typically observed on most coral reefs"
 
This is the common wisdom, but it may not be supported. From an upcoming article by me and Chris Jury:

"Two other recent studies have really begun to blow the lid off of what we thought we knew about the effects of elevated phosphate on corals. Godinot et al. (2011) examined the effects of phosphate concentration (0.00, 0.05, and 0.25 ppm) on growth and various physiological responses of the coral Stylophora pistillata. Similarly, Dunn et al. (2012) examined the effects of phosphate enrichment (0.09, 0.2, and 0.5 ppm) on the coral Acropora muricata. Both of these studies were performed in aquaria where at least some of the negative indirect effects of nutrient enrichment which can occur on a real coral reef, such as algal overgrowth, could be minimized. Surprisingly, in both studies the corals grew fastest at the highest phosphate concentrations tested (0.25 and 0.5 ppm, respectively). In fact, the rate of coral growth for both species increased linearly with the phosphate concentration. At least for A. muricata, skeletal density was also lowest for the rapidly-growing corals in the high phosphate concentration, though reduced skeletal density during periods of rapid growth is not necessarily unusual for corals. Hence, these corals were growing fastest and appeared to be “happier” at phosphate concentrations on the order of 5-10x greater than the commonly recommended upper limit for reef tanks, or about 10-50x the phosphate concentration typically observed on most coral reefs"

this does not surprise me, I run phosphates between .15 -.20 and have excellent growth and color, above .20 I start to see colors fade
 
It might eat Zoa's, might not.

Have you tried smothering the bryopsis? I have had success covering it with epoxy or superglue (it may take several applications).

yes, in fact that is my best weapon, I just cement over it and call it a day :)
 
I have always held for some Pi and nitrogen and argued against double zeros for these nutrients per many so called ulns methods but not as high as is been suggested. I get excellent color and growth with PO4 at .02 to .04ppm and NO3 at 0.2 to 0.5. Nuisance algae is almost non existent at these levels as well.
There is an occassional bit of bryopsis but in one of the frag tanks but it doesn't grow very much. I can usually kill off a patch with kalk paste a little at a time .
I'm not certain reduced skeletal density is a good thing but I'll wait for the article.BTW, Randy Farley let the the increased growth with elevated PO4 cat out of the bag a year or so ago.
 
I research things

I'm too lazy to dig around and find the rate. I will say the following, however. The reaction rate for the formation of lanthanum phosphate may be extremely fast (not ever formally "instantaneous"), but like all chemical reaction equilibria in a solution, the reaction rate to stoichiometric completion will depend on the concentration of the reactants present. This is the fundamental rate law as taught in first semester, or even high school AP, chemistry.
 
This is the common wisdom, but it may not be supported. From an upcoming article by me and Chris Jury:

"Two other recent studies have really begun to blow the lid off of what we thought we knew about the effects of elevated phosphate on corals. Godinot et al. (2011) examined the effects of phosphate concentration (0.00, 0.05, and 0.25 ppm) on growth and various physiological responses of the coral Stylophora pistillata. Similarly, Dunn et al. (2012) examined the effects of phosphate enrichment (0.09, 0.2, and 0.5 ppm) on the coral Acropora muricata. Both of these studies were performed in aquaria where at least some of the negative indirect effects of nutrient enrichment which can occur on a real coral reef, such as algal overgrowth, could be minimized. Surprisingly, in both studies the corals grew fastest at the highest phosphate concentrations tested (0.25 and 0.5 ppm, respectively). In fact, the rate of coral growth for both species increased linearly with the phosphate concentration. At least for A. muricata, skeletal density was also lowest for the rapidly-growing corals in the high phosphate concentration, though reduced skeletal density during periods of rapid growth is not necessarily unusual for corals. Hence, these corals were growing fastest and appeared to be "œhappier" at phosphate concentrations on the order of 5-10x greater than the commonly recommended upper limit for reef tanks, or about 10-50x the phosphate concentration typically observed on most coral reefs"
sounds like an interesting paper. No doubt that scleractinans such as Stylophora tolerate and perhaps even benefit from higher PO4 levels than many other stony corals. Looking forward to reading this.
 
Hey I have a question, Tom, Gary, ect. When I do a LC treatment on my tank I get the PO4 down to somewhere between 0.08 to 0.04 from a 0.25 heading on my Hanna checker. But a day or two later it moves back up. On 12-29 it was 0.09 after treatment, just checked again 0.27. Now I know your going to say "rock leaching" but I had the rock cooking in the basement for over a year. I'm not feeding because I don't have anything in the tank at present (total redoing), and I don't have algae as I am dosing vinegar. The only thing left is the gravel. The tank does get some natural sun light during the day.
I'm stumped why the PO4 goes right back up. Shouldn't the LC pull the phosphate out of the water and starve off whatever is causing the PO4 to rise? Would it help if I ran the LC on some consecutive days? Thanks,---Rick
 
I am not convinced that bounce back is from substrata release, and it may be an artifact of LC dosing. I have found that a constant small addition of LC results in a smaller or no bounce back, while an intermittent dosing can result in the kind of bounce back you are describing.
 
Hey I have a question, Tom, Gary, ect. When I do a LC treatment on my tank I get the PO4 down to somewhere between 0.08 to 0.04 from a 0.25 heading on my Hanna checker. But a day or two later it moves back up. On 12-29 it was 0.09 after treatment, just checked again 0.27. Now I know your going to say "rock leaching" but I had the rock cooking in the basement for over a year. I'm not feeding because I don't have anything in the tank at present (total redoing), and I don't have algae as I am dosing vinegar. The only thing left is the gravel. The tank does get some natural sun light during the day.
I'm stumped why the PO4 goes right back up. Shouldn't the LC pull the phosphate out of the water and starve off whatever is causing the PO4 to rise? Would it help if I ran the LC on some consecutive days? Thanks,---Rick

To piggy back this, if there was something leaching, wouldn't it eventually exhaust itself if you did the treatments over time? That is my hope. I scrubbed my rocks. LC came in today and just waiting on Hanna LR meter and dosing pump and I can get started.
 
The algae isn't necessarily getting its nutrients from the water column, and if your phosphate levels are bouncy, they may jump up soon. There are reports of phosphate levels bouncing back after significant drops due to LC dosing.


I am not convinced that bounce back is from substrata release, and it may be an artifact of LC dosing. I have found that a constant small addition of LC results in a smaller or no bounce back, while an intermittent dosing can result in the kind of bounce back you are describing.

I seen your earlier post regarding bounce back. Think I'll try another approach to dosing, and see what happens. Thanks,---Rick
 
I am not convinced that bounce back is from substrata release, and it may be an artifact of LC dosing. I have found that a constant small addition of LC results in a smaller or no bounce back, while an intermittent dosing can result in the kind of bounce back you are describing.
I agree, Richard.

This is probably the most compelling reason to dose LaCl3 into a constant side stream.
 
Hey I have a question, Tom, Gary, ect. When I do a LC treatment on my tank I get the PO4 down to somewhere between 0.08 to 0.04 from a 0.25 heading on my Hanna checker. But a day or two later it moves back up. On 12-29 it was 0.09 after treatment, just checked again 0.27. Now I know your going to say "rock leaching" but I had the rock cooking in the basement for over a year. I'm not feeding because I don't have anything in the tank at present (total redoing), and I don't have algae as I am dosing vinegar. The only thing left is the gravel. The tank does get some natural sun light during the day.
I'm stumped why the PO4 goes right back up. Shouldn't the LC pull the phosphate out of the water and starve off whatever is causing the PO4 to rise? Would it help if I ran the LC on some consecutive days? Thanks,---Rick

I am also having problems with PO4 bouncing back a day or two after dosing. I can only get it down to about 0.08ppm(Red Sea Pro) and then a day or two later it is back around 0.2-0.3ppm. I figured it was leaching from the rocks or sand but I have been dosing once or twice a week for over 2 months now without much change. I am also dosing vodka and nitrate has been steady at around 0.25ppm for about a month now.

I'm thinking about switching back over to GFO but am worried that will become really expensive.
 
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I think you hit the expensive part on the head. Seems a lot guys work their PO4 down with LC, and if they want it below 0.03 they turn to GFO.
I think I'm going to keep a continuous LC drip going for awhile and see if I can get the PO4 down and have it stay down on its own. I'm dosing vinegar and am thinking it must be leaching from my substrate. I'll post the outcome.---Rick
 
I am not convinced that bounce back is from substrata release, and it may be an artifact of LC dosing. I have found that a constant small addition of LC results in a smaller or no bounce back, while an intermittent dosing can result in the kind of bounce back you are describing.

That's interesting. I think a slow steady dose is likely more effective for a number of reasons .
However, since lanthanum PO4 is insoluble at reef pH I'm at a loss to imagine an artifact from the reaction that would put back PO4. Any idea how a bounce back in PO4 levels might be happening other than a bit of leaching from somewhere? It might be an artifact of the testing if some free lanthanum is in the sample water as might occur shortly after dosing.

Perhaps more of the lanthanum grabs carbonate when PO4 is very low but I don't think it would release any PO4 to do so.
I'd suspect that as the water PO4 species level drops ,some new equilibration from the substrate and other surfaces where orthophosphate is bound is ocurring.
It could be something else but I have no idea what that might be.
 
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