Brain twister, how much phosphate is there really in my reef tank mathematically?

[Ballyhoo]

I have been testing my phosphate quite a bit in the last couple of weeks or month using different test kits, Salifert , Hanna; my ranges started at .78 and gone down to .22 and varied somewhere in between Just depending on how I'm testing and when I'm testing it. I was trying to get an idea of really how much phosphate that would be if it was like a in test tube of pure phosphate, so I asked ChatGPT4 and this is the strangest thing it told me: I don't think it understands PPM, but in other context, it seems to understand what PPM is. maybe I just need to add four zeros to the equation. I have to brush up on my math. if you have .26 part per Millon of phosphate in a 52 gallon tank what fraction of a gallon or a liter is that end up being? ie what would be the total amount of phosphate in the tank?.

question to chatgpt4:
If there is a volume of 52 gallons of water with .26 ppm of phosphate, how much phosphate is that in liters?

Its answer:
To convert the volume of water from gallons to liters, you need to know that 1 gallon is approximately equal to 3.785 liters.

Given that there is 52 gallons of water, you can calculate the volume in liters:

52 gallons * 3.785 liters/gallon = 196.22 liters

Now, to calculate how much phosphate is in 196.22 liters of water with 0.26 ppm concentration, you can use the following formula:

Phosphate (in liters) = Volume of water (in liters) * Concentration (in ppm)

Phosphate = 196.22 liters * 0.26 ppm = 50.99 liters

Therefore, there would be approximately 50.99 liters of phosphate in 52 gallons of water with a concentration of 0.26 ppm.

 

[KStatefan]

ppm ≈ mg/L so 0.26 mg/L in your 196.22 liters would be 51 mg of phosphate in your tank.

 

[Randy Holmes-Farley]

First, I’ll say that such calculations may be interesting, but are not very useful. In many tanks, there may be far more bound to rock and sand than is free floating in the water, and when you try to remove it, you’ll need to remove the bound phosphate as well.

The factor might be 2x, 10x, or 250x as it was in an experiment in a few pounds of rock in a bucket.

 

[Ballyhoo]

First, I’ll say that such calculations may be interesting, but are not very useful. In many tanks, there may be far more bound to rock and sand than is free floating in the water, and when you try to remove it, you’ll need to remove the bound phosphate as well.

The factor might be 2x, 10x, or 250x as it was in an experiment in a few pounds of rock in a bucket.

well, then, when we take a water sample and test it, it's not telling us anything about what's bound to rock and sand or gravel? I mean, that actually seems obvious now that you mention it.

 

[Randy Holmes-Farley]

well, then, when we take a water sample and test it, it's not telling us anything about what's bound to rock and sand or gravel? I mean, that actually seems obvious now that you mention it.

That is correct. It tells you what is available to organisms, but not how much needs to be removed to successfully lower it .

 

[VintageReefer]

well, then, when we take a water sample and test it, it's not telling us anything about what's bound to rock and sand or gravel? I mean, that actually seems obvious now that you mention it.

Correct. And there is a balance in tank between what is free in the water and what is bound to objects. The test kits only test the water. It is referred to as an equilibrium

When you remove phosphate from the water, the outcome of a test will decrease. But you will see, in roughly 12-24 hours, a new test will show an increase. As you remove phosphate from the water, you disrupt the equilibrium, and allow phosphate to unbind from the rock and go back into free flowing water. As you add phosphate to the water, you will see a spike, and then it will go down somewhat as phosphate binds to objects.

As far as I know, there is no reasonable way to know how much phosphate is bound to your rock, sand, decorations, etc. but I know, for many people, it it A LOT. Randy’s estimates seem plausible to me

people…myself included, have spent days, weeks, or months, trying to truly bring down phosphate levels to a point where they don’t re-elevate and stay in the range someone wants them to be in

 

[Ballyhoo]

ppm ≈ mg/L so 0.26 mg/L in your 196.22 liters would be 51 mg of phosphate in your tank.

more on this: if phosphate is a soluble element then mg's can be converted into milliliters right? Or is phosphate not a soluble element?

Anyways, I hope this is my new solution until my tank matures down the line.
kind of running out of sump space. Also the manual for the reactor mentioned something about loop cords for plugs. But when LFS installed my reef tank, I don't think they did any loop cords. I know this is not chemistry. but I just had one extra outlet to plug in the reactor. i'm not sure the way I have the big power strip mounted into my cabinet wall underneath the tank in the area of the sump is safe long-term.

 

[Randy Holmes-Farley]

more on this: if phosphate is a soluble element then mg's can be converted into milliliters right? Or is phosphate not a soluble element?

Anyways, I hope this is my new solution until my tank matures down the line.
kind of running out of sump space. Also the manual for the reactor mentioned something about loop cords for plugs. But when LFS installed my reef tank, I don't think they did any loop cords. I know this is not chemistry. but I just had one extra outlet to plug in the reactor. i'm not sure the way I have the big power strip mounted into my cabinet wall underneath the tank in the area of the sump is safe long-term.

It is easy to convert ppm inorganic phosphate in the water into mg inorganic phosphate in the water.

1 ppm ~ 1 mg/L

 

[GARRIGA]

Are we trying to remove phosphates or maintain a certain level of equilibrium with rocks meaning 0.03 today isn't going to be 0.03 tomorrow even if no additional phosphates added because rocks absorbing and releasing constantly changing values. Unless there's a point of equilibrium where that removed only represents that added. For me that's the real brain twister.

 

[Randy Holmes-Farley]

Are we trying to remove phosphates or maintain a certain level of equilibrium with rocks meaning 0.03 today isn't going to be 0.03 tomorrow even if no additional phosphates added because rocks absorbing and releasing constantly changing values. Unless there's a point of equilibrium where that removed only represents that added. For me that's the real brain twister.

If you maintain a steady amount in the water, rocks will stop being a net source or sink. The amount bound directly relates to the water concentration.

 

[Ballyhoo]

can it be expected that a newer reef tank will have more fluctuations in aquaria non bound phosphate levels than a more established reef tank?

 

[Randy Holmes-Farley]

can it be expected that a newer reef tank will have more fluctuations in aquaria non bound phosphate levels than a more established reef tank?

If by fluctuations you mean levels changing significantly hour to hour or day to day, I am not sure why that would be a function of the tank age.

 

[Ballyhoo]

it's just often been said that parameters are less stable in new reef tanks and I was wondering if that applies to phosphate.

 

[Randy Holmes-Farley]

it's just often been said that parameters are less stable in new reef tanks and I was wondering if that applies to phosphate.

I agree that folks make claims about stability and age, but I do not know if it has a basis in reality post cycling, and if it does, what exactly it applies to. Some of these sorts of statements may apply to some specific situation but get so generalized and simplified that they lose meaning.

 

[Ballyhoo]

well, I thought as time goes on tanks become more stable and that's why they say like don't get SPS in a new tank

 

[Randy Holmes-Farley]

well, I thought as time goes on tanks become more stable and that's why they say like don't get SPS in a new tank

IMO, that is an overly simplistic assessment and in fact, the reason to wait may have nothing to do with measurable parameters, but with bacterial populations, organic levels and composition, husbandry experience, and other factors.

 

[klc]

.

 

[Ballyhoo]

IMO, that is an overly simplistic assessment and in fact, the reason to wait may have nothing to do with measurable parameters, but with bacterial populations, organic levels and composition, husbandry experience, and other factors.

husbandry factors aside, I have been most interested in trying to understand the process of beneficial biological change that occurs to coral reef tank overtime, for example, Coraline is often noted as a biological indicator of a mature tank. IDK whether Coraline itself is the beneficial flora, or just an indicator of other flora. That's what I'm really trying to investigate. What flora, what bacterial populations populate and imbed in a tank such that it makes for a tank to be more stable over time? Or is this more towards the husbandry side, which makes all the difference. but I'm reading so much that while everywhere I read it's people on the forums saying it took 123 years. But then I ran into a guy at a local coral shop last week and he said his tank which is size like mine was thriving in three months; but what he did was add a completely separate but obviously integrated refugium. maybe the guy is just much smarter than me. I would like to create a refugium But the way he did so was drilling a hole through a wall so he would never see refugium alongside his tank in the living room. In my case, it would have to be next to the tank and openly visible. I am still considering that option, though, like my main tank is the mother tank and maybe having a second tank connected to it as a refugium.

 

[Randy Holmes-Farley]

husbandry factors aside, I have been most interested in trying to understand the process of beneficial biological change that occurs to coral reef tank overtime, for example, Coraline is often noted as a biological indicator of a mature tank. IDK whether Coraline itself is the beneficial flora, or just an indicator of other flora. That's what I'm really trying to investigate. What flora, what bacterial populations populate and imbed in a tank such that it makes for a tank to be more stable over time? Or is this more towards the husbandry side, which makes all the difference. but I'm reading so much that while everywhere I read it's people on the forums saying it took 123 years. But then I ran into a guy at a local coral shop last week and he said his tank which is size like mine was thriving in three months; but what he did was add a completely separate but obviously integrated refugium. maybe the guy is just much smarter than me. I would like to create a refugium But the way he did so was drilling a hole through a wall so he would never see refugium alongside his tank in the living room. In my case, it would have to be next to the tank and openly visible. I am still considering that option, though, like my main tank is the mother tank and maybe having a second tank connected to it as a refugium.

I do not know what factors, if any, change in a reef tank over weeks and months to make if more suitable for organisms. Certainly, microorganism populations change, but is that the critical event? Does it matter at all?I’m not entirely sure there is anything in tank that changes in a critical way.

Like a new driver scenario, a car is safer to ride in with a driver that has 3 months experience than in one that has 5 minutes of experience. How much that matters for reef tanks, I do not know.

But it is always reasonable to challenge assertions about vague rules relating to reefs and asking what is the evidence that the rule is accurate, and if so, why.