Do these Phosphate numbers indicate leeching?

[Dom]

10/12 - PO4 = .46
- Water Change

10/13 - PO4 = .40

10/14 - PO4 = .46

The increase from .40 to .46 can't be from one day of feeding, can it? And this happened while running a scrubber and Phosguard.

I feel like it is a big jump for 24 hours, so I attributed it to leeching.

Feedback is appreciated.

 

[Dan_P]

10/12 - PO4 = .46
- Water Change

10/13 - PO4 = .40

10/14 - PO4 = .46

The increase from .40 to .46 can't be from one day of feeding, can it? And this happened while running a scrubber and Phosguard.

I feel like it is a big jump for 24 hours, so I attributed it to leeching.

Feedback is appreciated.

For phosphate to leach, the system would have had to be exposed to phosphate much higher than 0.4 for some time.

A 0.06 ppm difference is pretty close to noise in the data (not just variation in the analytical method but also the amount of interfering particulates. Since you notice these changes after a water change, a disturbed substrate could have suspended particulates in the water). I think you do not have enough data to reject null hypothesis which in this case is “no real change occurred”.

If the change is real, you can’t eliminate feeding as the cause unless you know how much phosphate is being added by the food.

Phosguard does not act instantaneously. Also, do you know whether the Phosguard is working? How well. It being present or nor doesn’t help us..

Since the phosphate concentration change is small, it would be a good idea to confirm that it is real. Repeat the phosphate measurement three times during the day, morning, afternoon, and evening.

 

[Dom]

For phosphate to leach, the system would have had to be exposed to phosphate much higher than 0.4 for some time.

A 0.06 ppm difference is pretty close to noise in the data (not just variation in the analytical method but also the amount of interfering particulates. Since you notice these changes after a water change, a disturbed substrate could have suspended particulates in the water). I think you do not have enough data to reject null hypothesis which in this case is “no real change occurred”.

If the change is real, you can’t eliminate feeding as the cause unless you know how much phosphate is being added by the food.

Phosguard does not act instantaneously. Also, do you know whether the Phosguard is working? How well. It being present or nor doesn’t help us..

Since the phosphate concentration change is small, it would be a good idea to confirm that it is real. Repeat the phosphate measurement three times during the day, morning, afternoon, and evening.

Good morning.

Yes, I've posted PO4 as high as .98 in threads. I installed a Santa Monica turf scrubber, which after 8 months, has begun to produce. The Phosguard was an added layer of PO4 control.

Yes, when I look at it, I realize that .06 isn't really that big of a change.

That the Phosguard may be exhausted has occurred to me. But I need more testing to make this determination.

I began running the Phosguard reactor for 6 hours daily and increased gradually. I'm trying to dial it in much in the same way I would dial in a dosing pump. I try not to run it more than necessary to minimize the aluminum. I manage the aluminum through water changes.

Will I see changes in PO4 that quickly from morning, to afternoon, to evening?

 

[exnisstech]

Far from an expert but I don't think GFO lasts very long. I've had GFO in a reactor become exhausted in 24hrs.
Apologies if phosguard is different than typical gfo, I've only used rowaphos

 

[Miami Reef]

I agree. With high phosphate levels and good flow through the media, GFO is likely fully saturated within a day.

 

[BZOFIQ]

... I've had GFO in a reactor become exhausted in 24hrs.
...

I agree. With high phosphate levels and good flow through the media, GFO is likely fully saturated within a day.

One day???

I've found RowaPhos to last much longer and I too was leaching phosphates with readings in the .99 range when I moved LR from my temp system.

 

[Timfish]

Besides removing various forms of phosphorus from the water as they feed, corals also put various forms back into the water. Depending on multiple variables, changes could be from corals not feeding as well leaving more PO4 in the water, or, feeding on forms that give them an excess of PO4 they release back into the water.

Biofilms and sponges are also messing with PO4 so disturbing them has the potential of altering PO4 numbers.

Here's Fig. 4 from this paper on phosphorus metabolism



FWIW .03 mg/l is the threshold level to prevent phosphorus limitation in corals, identified by researchers at Southampton University in England using corals maintained in an aquarium for about a decade. .3 mg/l is what corals are subjected to with upwelling in the ocean. .5 mg/l might be acceptable for some as acros have been shown to increase growth up to this level. FWIW .9mg/l is the level the Steinhart Aqaurium's ex situ sexually reproduced acro colonies are being grown out with. Rich Ross's (who's part of the team at Steinhart) has his acro dominate mixed reef sitting at 1.8 mg/l, his tank can be seen at the beginning of his MACNA presentation on phosphate.

 

[exnisstech]

One day???

I've found RowaPhos to last much longer and I too was leaching phosphates with readings in the .99 range when I moved LR from my temp system.

I've had it deplete in 24 hrs more than once and is why I always run about 25% of the recommended amount to prevent it from stripping the PO4 to quickly. I don't think mine was leeching from rocks tho but from over feeding. Maybe it can last longer if the PO4 is slowly leaching vs being added by food? Or maybe if I added the amount called for it would last longer but as mentioned I do not want to lower it too quickly.

 

[Quietman]

You could try some Lanthanum Chloride. Knock the PO4 down to less than 0.1 and then you can tell if it pops back up quickly to previous levels. I've used it alone and with Phosguard when I've forgotten to test or change out the minimal amount of Phosguard I used. I like using a gentle media (not GFO) to stretch out times before I used LaCl as it is pretty potent. But still after years, no harm to livestock but I maybe used it 2-3 times a year when PO4 popped to >.1.

Powerful stuff, go slow (start with 1/2 dose or less, and only shoot for .1 at a time per day or two). Dose at night. Works in just a few hours so very easy to tell what's reducing the PO4. Plus it's repeatable, meaning that so many drops will reduce your PO4 a consistent amount. Very helpful I've found.

 

[BZOFIQ]

...


FWIW .03 mg/l is the threshold level to prevent phosphorus limitation in corals, identified by researchers at Southampton University in England using corals maintained in an aquarium for about a decade. .3 mg/l is what corals are subjected to with upwelling in the ocean. .5 mg/l might be acceptable for some as acros have been shown to increase growth up to this level. FWIW .9mg/l is the level the Steinhart Aqaurium's ex situ sexually reproduced acro colonies are being grown out with. Rich Ross's (who's part of the team at Steinhart) has his acro dominate mixed reef sitting at 1.8 mg/l, his tank can be seen at the beginning of his MACNA presentation on phosphate.

It's because of this info I don't wig out too much with my phosphates - there is no algae in the tank. What needed to leach, already leached and was absorbed. I feed heavily with my automatic feeder (6 times a day) and they get a large cube of frozen Mysis daily.

Here is my historical for what the AF can show.

I just added 5 full tablespoons of RowaPhos to the system (350G+ total volume) this weekend, will see where its heading when I re-test this Saturday but I'm sure I am not depleting this media within days or weeks.

 

[Dom]

For me, PO4 control is still a work in progress. I'm still trying to better understand the PO4 in our tanks.

Ultimately, I would like to use the scrubber exclusively for PO4 control.

One day? I'm surprised to hear this.

 

[exnisstech]

One day? I'm surprised to hear this

I guess with high levels it can happen as @Miami Reef stated and Randy confirmed on another site.

 

[Dom]

I guess with high levels it can happen as @Miami Reef stated and Randy confirmed on another site.

I believe you, just surprised is all.

 

[BryanM]

10/12 - PO4 = .46
- Water Change

10/13 - PO4 = .40

10/14 - PO4 = .46

The increase from .40 to .46 can't be from one day of feeding, can it? And this happened while running a scrubber and Phosguard.

I feel like it is a big jump for 24 hours, so I attributed it to leeching.

Feedback is appreciated.

It also might depend on your feeding schedule and what you feed. Lots of people report frozen foods add a ton of phosphates unless rinsed as an example.

I'm also on the bandwagon that GFO gets depleted rather quickly.... Another reason it is an expensive option, but its a ton safer than lanthanum chloride.

I am a Surf4 ATS user, and I'm guessing right now that it is doing the job, but I need more time and tests to really know. I might need to upgrade to the 4x (as I got a substantially larger tank than when I bought the 4)

 

[Dom]

It also might depend on your feeding schedule and what you feed. Lots of people report frozen foods add a ton of phosphates unless rinsed as an example.

I'm also on the bandwagon that GFO gets depleted rather quickly.... Another reason it is an expensive option, but its a ton safer than lanthanum chloride.

I am a Surf4 ATS user, and I'm guessing right now that it is doing the job, but I need more time and tests to really know. I might need to upgrade to the 4x (as I got a substantially larger tank than when I bought the 4)

Where feeding is concerned, I've always been of the impression that dry, processed foods are a higher source of PO4 than the frozen. There was a time when I was rinsing my frozen food feedings. But then I got this idea in my head that placing it in the tank, in its entirety, would provide nutrition to filter feeders. But I couldn't tell you for sure if that is correct.

Yes; I am quite surprised to hear that GFO depletes so quickly.

When I first began reading up on Santa Monica Filtration and their products, I was looking for products sized to my 125 gallon. But this is wrong. The correct way to determine the right size is to base it on the number of cubes you feed daily. When I spoke with support, the gentleman made his recommendation based on that info.

I think of reducing phosphates as weight loss. As long as you have more calories going out than coming in, you'll lose weight. I would say SM confirmed this trying to determine that the device they recommend removes more phosphate than I put in, daily.

 

[exnisstech]

How's your scrubber growth? I don't think the ATS is a cure all for PO4 but it seems to be helping now that I have mine producing again.
This is 6 days growth in 16oz container.

 

[BryanM]

I think of reducing phosphates as weight loss. As long as you have more calories going out than coming in, you'll lose weight. I would say SM confirmed this trying to determine that the device they recommend removes more phosphate than I put in, daily.

Agreed, and tank size meant more fish, more corals, etc.

Also, they are not cheap, so I asked about over sizing it and just controlling the grow with a light schedule, which seemed more optimal than not.

But I had not foreseen the road I went down: FB Marketplace RS 450xl+equipment, woot great deal (First tank in 25 years) -> Setup, happiness, found Reef2reef -> Stumbled upon seam failure thread. Pause. Google. Sadness. -> Waterbox 230.6 replacement.

That's how I got where I'm at :) All that said I need to test phos tonight and see what the last round of roughly 1/2 the GFO I've been adding and the previous .23 result is at now. I'm not mad at .23, I'm just hoping its not still slowly creeping up, which if it is, I feel like I might need more ATS. I do not want to run gfo all the time, expensive.

 

[Miami Reef]

Just to be clear, the N and P in foods are not impurities. They are integral ingredients of the biomolecules in tissue based foods and cannot be removed. For example, there is at least one and often 2 or more nitrogen molecules in every amino acid in every protein, and those will end up as nitrate if the protein is metabolized.

Similarly, phosphate is part of many biomolecules in every cell, such as DNA, RNA, phospholipids, and many proteins.

IF you use a food that contains fish meal, then it may contain excess phosphate due to bones, which have a lot of phosphorus in them.

I show the phosphorus levels in many foods here:

Aquarium Chemistry: Phosphate And Math: Yes You Need To Understand Both
https://www.advancedaquarist.com/2012/3/chemistry

That’s an interesting quote from Randy ^

 

[Dom]

How's your scrubber growth? I don't think the ATS is a cure all for PO4 but it seems to be helping now that I have mine producing again.
This is 6 days growth in 16oz container.

Yes; that does look like what was beginning to grow. I will have to take a closer look and let you know.

 

[BZOFIQ]

I guess with high levels it can happen as @Miami Reef stated and Randy confirmed on another site.

Not disagreeing with people who exhausted their media in one day.....


Question is what is considered "substantially elevated" and even then it would depend how much media was used per volume of water filtered.

In other words if you use 2 table spoons of media in a 400 gallon system that is at .99+ then yeah I can see that.