sand substrates

Hi All,
I have a couple quick questions about builders sand, a.k.a. "leveling sand"
that you can buy at the home improvement store.
It is C-33 - what does that mean?
The data sheet says it is at least 99% SiO2 in the form of silica and
crushed quartz. I was attracted to the sand because it looked to have the
right size grains and a nice uniform color - very pretty.
I poured vinegar on it and it did not bubble at all.
So I put a couple scoops into a 5 gallon bucket (probably 5 inches on sand
in the bottom of the bucket). Then I poured water in the bucket and I was
amazed at the opacity of the water. The water was a peach color.
Subsequent rinsings turned the water clear. Why was it so peach colored - I
was wondering if there was maybe red clay in there? Could the yellow-peach
color be the tiny perccentage of non-Si02? Is this normal?

Thanks!
Jen

Aquarijen wrote:

Hi All,
I have a couple quick questions about builders sand, a.k.a. "leveling sand"
that you can buy at the home improvement store.
It is C-33 - what does that mean?
The data sheet says it is at least 99% SiO2 in the form of silica and
crushed quartz. I was attracted to the sand because it looked to have the
right size grains and a nice uniform color - very pretty.
I poured vinegar on it and it did not bubble at all.
So I put a couple scoops into a 5 gallon bucket (probably 5 inches on sand
in the bottom of the bucket). Then I poured water in the bucket and I was
amazed at the opacity of the water. The water was a peach color.
Subsequent rinsings turned the water clear. Why was it so peach colored - I
was wondering if there was maybe red clay in there? Could the yellow-peach
color be the tiny perccentage of non-Si02? Is this normal?

Thanks!
Jen

Silicates will play havock in your tank, you will get a brown algae (diatoms)
bloom in no time at all! Silicates will leach from this type of sand!

Thusly Geezer From The Freezer Spake Unto All:

Silicates will play havock in your tank, you will get a brown algae (diatoms)
bloom in no time at all! Silicates will leach from this type of sand!

No.
While it is true that very small amounts of silica will leach from the
sand and from the glass, diatoms are very, very, rarely limited by
silicates in coastal seawater, and virtually never in freshwater.
Unless your aquarium is using nothing but pure RO, they're not going
to be silica limited, and any addition of silica will make no
difference at all.

Also I might point out that there are basically two types of sand one
might use in aquaria: there's carbonated-based sand (limestone), which
buffers pH to 7.5-7.7, and there's silicate-based sand which is almost
entirely inert, does not affect pH, but does leak trace amounts of
silica. Silicate-based sands are by far the most common in freshwater
aquaria.

"Mean_Chlorine" wrote in message No.
While it is true that very small amounts of silica will leach from the
sand and from the glass, diatoms are very, very, rarely limited by
silicates in coastal seawater, and virtually never in freshwater.
Unless your aquarium is using nothing but pure RO, they're not going
to be silica limited, and any addition of silica will make no
difference at all.

Also I might point out that there are basically two types of sand one
might use in aquaria: there's carbonated-based sand (limestone), which
buffers pH to 7.5-7.7, and there's silicate-based sand which is almost
entirely inert, does not affect pH, but does leak trace amounts of
silica. Silicate-based sands are by far the most common in freshwater
aquaria.



A agree with MC on this. I have a Tanganyika tank with beach sand that is
renowned for high silicates and I have zero algae problems with this setup.
--
**So long, and thanks for all the fish!**

"Happy'Cam'per" wrote in message
...
"Mean_Chlorine" wrote in message No.
While it is true that very small amounts of silica will leach from the
sand and from the glass, diatoms are very, very, rarely limited by
silicates in coastal seawater, and virtually never in freshwater.
Unless your aquarium is using nothing but pure RO, they're not going
to be silica limited, and any addition of silica will make no
difference at all.

Also I might point out that there are basically two types of sand one
might use in aquaria: there's carbonated-based sand (limestone), which
buffers pH to 7.5-7.7, and there's silicate-based sand which is almost
entirely inert, does not affect pH, but does leak trace amounts of
silica. Silicate-based sands are by far the most common in freshwater
aquaria.



A agree with MC on this. I have a Tanganyika tank with beach sand that is
renowned for high silicates and I have zero algae problems with this
setup.
--
**So long, and thanks for all the fish!**

I have read the pros and cons of having silica sand as a substrate - I don't
want to raise my pH (it is not a cichlid tank) but need sand for my fire eel
(he digs a lot and I'm afraid he'll get hurt on my chunky gravel) and I like
how it looks. So I'm sold on silica sand...

That said, how many times did you all have to rince your sand - mine is very
yellow-peach colored. I called the industrial studies department of my old
university and they said the yellow color was probably the "fines" in the
sand and that it would wash out. Anybody else come accross this?
Thanks!
Jen

Happy'Cam'per wrote:
A agree with MC on this. I have a Tanganyika tank with beach sand that is
renowned for high silicates and I have zero algae problems with this setup.
--
**So long, and thanks for all the fish!**

Diatoms feed on silicates, phosphates and nitrates period!
You must have awesome lighting or none of the above in your
tank.

Thusly Geezer From The Freezer Spake Unto All:

Diatoms feed on silicates, phosphates and nitrates period!
You must have awesome lighting or none of the above in your
tank.

All aquaria using tapwater have the silicates, and most aquaria have
all three.

That silicates lead to diatom blooms is a myth.

I wish it did, because then it would be easy for me to get diatoms to
feed my shrimp larvae, but it doesn't.

Geezer From The Freezer wrote:


Silicates will play havock in your tank, you will get a brown algae (diatoms)
bloom in no time at all! Silicates will leach from this type of sand!

Your tank is made mainly from silica, glass is a mixture of SiO2 with
various other oxides (Na, K, Ca, B) mixed in to lower the melting point.
Also, silicic acid is a common compound in water.

Phosphate and nitrate are more of a problem, though.