[quote="Stefan"]Fosfat kan sagtens hobe sig op i sandbund og sten.
Den største del af fosfaten er bla bundet i vores sten.
Prøv at læse denne artikkel.
Det er værd at tygge sig igennem den. Det forklarer bla hvorfor vi har PO4 selvom vi ikke kan måle det.
Den sidder nemlig i stenene, den organiske PO4
The No-Nonsense Guide to Preventing and Curing Nuisance Algae Outbreaks
8 | P a g e
Chapter 2: The Big Building Block of
Algae
Algae, just like any living organisms, need certain things to grow. To be more specific,
algae need four main components to grow:
light
carbon
nitrogen
phosphate
Besides light, we’re going to make the assertion that phosphate is the most important
building block of algae.
The reason we’re making this assertion is that phosphates have the most potential to build
up in your saltwater tank. And phosphate is the building block of algae that is most
easily targeted by you as a saltwater tank owner.
NOTE: Light is by far the easiest building block of algae to manage. Just flip a switch
and you can turn light on/off. However, no one wants to stare at a dark saltwater tank all
day! On top of that fact, if you want to keep corals in your tank, the corals need light so
having no light over your tank isn’t an option!
So while light is the easiest to manage, you’re not going to keep your lights off all the
time. Focusing on controlling light, to therefore control algae, isn’t worth much effort.
That brings us back to phosphates.
Think about how many times you’ve heard people talk about keeping your phosphates
low in your tank. Mr. Saltwater Tank even made two whole Mr. Saltwater Tank TV
shows on it! Then go look at all the various phosphate-removing medias on the market.
Any local fish store or online retailer will have several offerings for products that claim
to remove phosphates from your tank. It seems that everyone is phosphate crazy!
Why is everyone so phosphate crazy? To understand why, you have to first understand
more about phosphates.
Phosphates 101
In your saltwater tank, phosphates mainly occur in 2 main forms:
- Soluble Reactive Phosphates (SRP)
- Organic Phosphates
The No-Nonsense Guide to Preventing and Curing Nuisance Algae Outbreaks
9 | P a g e
Soluble reactive phosphates are also known as orthophosphates and to keep things easy,
we’ll refer to them as SRPs throughout the rest of this guide.
SRP is an inorganic form of phosphate. In everyday language, that means that SRP is a
simple form of phosphate that is dissolved in your tank’s water and easily used by algae
and bacteria. While this might be the first time you’ve heard of SRPs, you’ve actually
been giving SRPs a lot of attention!
You’re probably saying to yourself,
“When in the heck have I ever paid attention to SRPs?!”
Here’s when:
Whenever you run a phosphate
test on your tank, you are measuring SRPs.
In fact, without really expensive scientific gear, SRPs are the only phosphates you can
measure in your tank.
Therefore, given that SRPs are used by algae and are the only kind you can easily
measure, it makes sense that you and everyone else give them so much attention! They
are the source of all your algae problems…right?
Wrong.
We hate to be the bearer of bad news, but we have to tell you that SRPs may account for
less than 2% of all the phosphates in your tank. That means you are giving a lot of
attention to something that isn’t overly prevalent in your tank!
SRPs are important however, and we’ll dive more into them in a later chapter. For now,
understand what they are – phosphates that are dissolved in your tank’s water - and that
you’ve only been testing for SRPs when you run a phosphate
test.
The other main form of phosphates in your tank is organic phosphates.
Organic Phosphates
Organic phosphates are phosphates that are bound to
or incorporated in organic material, instead of being
soluble in the water like the SRPs. Imagine a brick
wall that is made up of lots of red bricks and just a
few green bricks. The green bricks are phosphates
and the red bricks are organic matter. So as long as
the green bricks are part of the brick wall, they are
bound to the red bricks and can’t be easily removed.
If we told you to remove a single green brick, you’d
Figure 2 Organic Phosphates
The No-Nonsense Guide to Preventing and Curing Nuisance Algae Outbreaks
10 | P a g e
have to do a lot of work to extract just one green brick.
That means organic phosphates are more complex and harder to breakdown than SRPs, as
the organic phosphates first have to be removed from the organic matter (in our case, the
brick wall) before they can be removed from your tank. Also, since organic phosphates
are part of the organic material, that means you can’t
test for them in your tank because
your
test kit only measures phosphates dissolved in your tank’s water (hint: SRPs). Given
that fact, you now understand why your phosphate
test kit only measures SRPs! This fact
also shows you that counting on your
test kit as an overall measure of phosphates in your
tank is horribly inaccurate.
You can measure organic phosphates, but not without really expensive and fancy
equipment that most aquarists don’t have and likely won’t be willing to purchase.
We’ll come back to organic phosphates later. For now, know that they are much more
prevalent than SRPs, and that you can’t easily
test for organic phosphates.
Phosphates: I’m a big P and you can’t ignore me
Make no mistake, phosphates cannot be ignored in a saltwater tank, especially when it
comes to battling nuisance algae. If you have phosphates, you’ve something that algae
need (and badly want) to grow. No wonder everyone is phosphate crazy!
Can we really blame them though? Nuisance algae are just what the name says – a
nuisance. It looks horrible even though your non-saltwater tank friends will look at your
algae-infested tank and say, “It’s so pretty!”
As saltwater tank hobbyists, we hate nuisance algae and phosphates and we’ll go to great
lengths to keep them out of our tanks. However, the thought of never having any
phosphates in your tank is futile.
The tank is closed, so how did all this phosphate get in here?!
One of the most frustrating parts of owning a saltwater tank is wondering how things like
algae can suddenly appear in your tank when you didn’t deliberately put them in there.
Phosphates seem to fall into the same category: One day you have zero phosphates in
your tank, and the next day,
“WHAM!”
Phosphates show up!
So where did they come from if you aren’t dosing phosphates?
The answer: lots of places.
The No-Nonsense Guide to Preventing and Curing Nuisance Algae Outbreaks
11 | P a g e
Phosphates Source #1: Fish Food
Any fish food will contain phosphates. And that’s not a bad thing. Your fish need
phosphates as part of their diet, so a fish food containing phosphates is doing its job.
The problem occurs when you feed so much food that your fish can’t eat it all. When
your fish don’t eat the food, it begins to break down in your tank, which can drive up
phosphate levels as well as nitrate levels. If you feed frequently, then you have a
constant source of phosphates going into your tank. Since your tank is a closed system
(nothing gets in or out of it unless you put it in, or take it out), the phosphates will
continue to build unless you do a water change, adding phosphate-removing media, or
algae start to grow and consume the phosphates.
We’re not encouraging you to NOT feed your fish. We just want you to be aware that
fish food is a double-edged sword. Your fish need food, and overloading your tank with
it is bad.
Add in the potentially tank-trashing activities such as feeding corals or dosing your tank
with phytoplankton, and you’ve got even more phosphates to go around.
Phosphates Source #2: Water
Tap water can contain phosphates and yes, you have to fill your tank with water
somehow. How do you remove phosphates from the water going into your tank?
The answer: You purify it with a Reverse Osmosis and DeIonization (RODI) filter.
Properly purified RODI water will contain zero phosphates, which means every time you
do a water change, or top off your tank to replace evaporated water, you won’t be
dumping phosphates into your tank. Remember that you are dealing with a closed
system, so if you are constantly putting in tap water with high phosphates, these
phosphates will build up in your tank and cause issues like algae outbreaks.
Phosphates Source #3: Bad Rock
As mentioned before, organic phosphates are phosphates locked in organic matter, and
one of the biggest sources of organic matter in your tank is your live rock.
NOTE: Before someone draws a conclusion from the above statement, we’re NOT
saying the presence of organic matter means you have organic phosphates.
Due to its highly organic nature, live rock can be a great harbor for phosphates. Take for
example, rock that was in a tank that had persistently high phosphates. These phosphates
were likely used by algae in the tank; the excess phosphates had to go somewhere and the
rock made for a great home. Over time, the amount of phosphates in the rock increased
The No-Nonsense Guide to Preventing and Curing Nuisance Algae Outbreaks
12 | P a g e
Fik du læst den?
Den er god at få visdom af.
Erik