Phosphates

[wasp]

Don't agree with all that. In a lightly stocked tank a skimmer may suffice, but in a heavily stocked tank more than just a skimmer alone is required.

[wasp]

A skimmer is capable of removing more phosphate than any iron based remover is capable of.

You sure about that?

[lduncan]

Maybe you need to find a way of getting the crap to the skimmer so it can be removed permanently?

[wasp]

Maybe you need to find a way of getting the crap to the skimmer so it can be removed permanently?

Indeed, that is the best option. However you will never get ALL the crap to the skimmer. In a heavily stocked tank more than a skimmer alone is likely required.

[lduncan]

You sure about that?

Well think of it like this. A skimmer can remove the most abundant forms of phosphate, organic phosphate, efficiently.

Chemical media is most efficient at removing the forms which occur in larger quantities only once organic phosphate is packed to overflowing in the system.

And it just happens that the chemical media remove the only forms which our test kits test for, so it seems to do the job faster and better.

What happens when the chemical media have absorbed all the inorganic phosphate? There's still all that organic stuff left, but it's not so good at holding on to that type. A skimmer's going to easily outperform it.

Also the skimmer is permanently removing it from circulation immediately. With media, the stuff is still in the circulation path, and can be attacked and liberated again by organisms.

Layton

[reef]

i dont beleive that a skimmer will remove all po4,

so if i dont pump any water to my skimmwer and leave it running for a few days the po4 should be zero.?

I thought a skimmer removes waste before it can turn to po4

[lduncan]

Well it doesn't remove inorganic phosphate directly. What it does is remove phyto and bacteria, along with the phosphate that it has bound. Then ofcourse, through reproduction, more bacteria and phyto grows to replace it, as it grows it absorbs any inorganic phosphate which is around, only to be skimmed and removed.

So what it does is remove the largest source of phosphate (that bound in phyto and bacteria) which results in any excess inorganic phosphate being reduced as well, as long as the export is large enough.

Chemical media doesn't do this very well.

Layton

[wasp]

A well reasoned argument Layton, and I agree with most of it. However -

Well think of it like this. A skimmer can remove the most abundant forms of phosphate, organic phosphate, efficiently.Layton

Agreed

Chemical media is most efficient at removing the forms which occur in larger quantities only once organic phosphate is packed to overflowing in the system.

Agreed, to a point. Depends what media, Rowaphos is a good one. Also organic phosphate does not have to be "packed to overflowing" before orthophosphate can exist.

And it just happens that the chemical media remove the only forms which our test kits test for, so it seems to do the job faster and better.Layton

Agreed

What happens when the chemical media have absorbed all the inorganic phosphate? Layton

The phosphate in the tank is continuously changing from one form to another. If all orthophosphate is removed, it won't be long till some bound phosphate is converted to orthophosphate, once again suitable for removal by a phosphate binder.

Also the skimmer is permanently removing it from circulation immediately. With media, the stuff is still in the circulation path, and can be attacked and liberated again by organisms.Layton

Correct, what a skimmer removes is gone. Incorrect about Media though, once bound by Rowaphos, the phosphate will not be released back to the tank, under normal conditions that exist in a tank.

[lduncan]

Ok just a few clarifications. We've been through the orthophosphate not existing until organic sinks are full thing before.

And for all intents and purposes it's true. Just like you require bacteria to grab and hold/convert ammonia as soon as it's formed in the tank, bacteria will do a similar thing with phosphate, they will grab it as long as they have enough storage room (they grab much more than they need to support themselves). There are going to be trace amounts of orthophosphate floating around in transition, just like there is ammonia, but if the sinks are not full it's not going to be around for long and it's not going to be even close to detectable. When the sinks are full, it has more of a chance to float around before it is sequestered by something, or bumps into some media.

This tiny amount of transitional inorganic phosphate has to dodge a mine field of bacteria and phyto, and then literally smack into the media to even have a chance of being held. In the scheme of things it's insignificant until the sinks become full.

As for media not releasing phosphate back, it's got no choice in the matter. Bacteria are capable of freeing it, they have to be able to get it, and get it quickly. Just imagine if they couldn't for a second, that would mean that life sustaining elements like phosphorous would have been bound up in inert substances long ago.

Layton

[reef]

So if you have a bigger skimmer then it will remove bacteria quicker so you will also remove po4 as it is attached to the bacteria,

However if your skimmer was too big them will it not remove the bacteria too quick so it will not reproduce fast enough to remove po4?

[wasp]

Ok just a few clarifications. We've been through the orthophosphate not existing until organic sinks are full thing before.Layton

Just to regurgitate what someone else told me :lol: :-

QUOTE

"Phosphorus can also take other inorganic forms, such as the polyphosphates which are rings and chains of phosphate ions strung together by P-O-P bonds. While these are not significant in natural seawater, they can be present in things that get added to our tanks. There are many of these compounds, but most will likely break down into orthophosphate when added to a reef tank."

UNQUOTE

[lduncan]

From Randy the chemist per chance? Think bacteria, bacteria, bacteria.

[reef]

So if you have a bigger skimmer then it will remove bacteria quicker so you will also remove po4 as it is attached to the bacteria,

However if your skimmer was too big them will it not remove the bacteria too quick so it will not reproduce fast enough to remove po4?

??

[wasp]

Layton, remember I don't dissagree with much of what you say. Bacteria ROCK, which is why I use the Zeovit system.

But from my own experience in BZ days ( that's Before Zeovit :lol: ), I completely cleaned up an algae ridden tank with iron based phosphate remover. There is no doubt it can be done. Sure it only removes orthophosphate. No worries. Once all orthophosphate is removed more will be created from other forms, as per Randy. And in this way all phosphate can be reduced.

[wasp]

So if you have a bigger skimmer then it will remove bacteria quicker so you will also remove po4 as it is attached to the bacteria,

However if your skimmer was too big them will it not remove the bacteria too quick so it will not reproduce fast enough to remove po4?

Your comments layton?

[reef]

Must be a good question

[wasp]

[lduncan]

Jeez this zeovit stuff is looking more and more religous (must be the American influence) BZ, I don't know

Free organic phosphate is only converted to inorganic phosphate because an organism needs it in that form so it can use it. They don't go around converting free organic phosphate for the benefit of anything else. It's for them. It's not like Le Châtelier's principle in chemical equilibrium. I still maintain that inorganic phosphate only shows up in significant quantities when the sinks are full.

I think I get what reef is trying to say in that second part, but it doesn't really make sense as written. What I think he's asking is is it possible to skim so much bacteria so quickly that there is not enough remaining in the tank to reproduce fast enough for the skimmer?

I would guess the answer would be no. Most bacteria are fast at reproducing, especially when the conditions are favourable. There are a multitude of bacteria not only in the water, but also on the surfaces in the tank, i'd say these fixed bacteria are more than capable of reproducing fast enough to keep up with the most efficient skimmers.

Layton

[wasp]

Well your argument appears to make sense Layton. Problem is though that if it was true then it would not be possible to clean up a tank via the use of phosphate binding resins. In reality this is not the case.

Bottom line for me, after all the theory has been talked through, the proof is in the pudding.

[lduncan]

Well that depends what source is fuelling the algae, it it orthophosphate in the water, or is it organic phosphate in the rock?

From the same article you quoted above:

An important point about organic phosphates is that they will mostly not be impacted by phosphate-binding materials sold to the aquarium hobby. Consequently, while these products may do a fine job of reducing inorganic orthophosphate, they may not help an algae problem that is caused primarily by organic phosphates.

And what if it's not the phosphate reduction which is clearing the algae when using chemical media?

Layton

[reef]

Indeed iron base removers will also remove organics other than po4.

Still bottom line for me is i cant get away from only using a skimmer to remove po4.

Rowaphos it is until something better.

[wasp]

BZ, I don't know Layton

Ha Ha! I put that one there just for you! :lol:

Well that depends what source is fuelling the algae, it it orthophosphate in the water, or is it organic phosphate in the rock?

Layton

It will likely be both, or more correctly, both will be involved.

And what if it's not the phosphate reduction which is clearing the algae when using chemical media?Layton

Good point, something to consider.

[wasp]

As for media not releasing phosphate back, it's got no choice in the matter. Bacteria are capable of freeing it, they have to be able to get it, and get it quickly. Just imagine if they couldn't for a second, that would mean that life sustaining elements like phosphorous would have been bound up in inert substances long ago.

Layton

Just to once again regurgitate what somebody told me :lol:

This time quoted from Marine Depot web site, info supplied by the manufacturer.

"RowaPhos will absorb phosphate, silicates and arsenic. It is entirely safe in both fresh and saltwater systems. It does not release, when exhausted, any chemicals back into the water. ie phosphate, silicates or arsenic."

[lduncan]

It may not release it voluntarily, but bacteria sure can steal it.

[wasp]

Let's say you're right, bacteria can steal it. ( Although this would contradict the manufacturer ).

So we have fully saturated media, then bacteria "steal" some of the phosphate. The media would presumably now be not saturated, and ready to grab the next bit of orthophosphate that comes along.

So all up, still doing the job.