I need some stainless steel rods to act as water level sensor probes for
my fishtank, does anyone know where I can get hold of some?


--
Posted via Mailgate.ORG Server - http://www.Mailgate.ORG

On Thu, 22 Jul 2004 10:15:10 +0000 (UTC), "Lawrence Zarb"
wrote:

I need some stainless steel rods to act as water level sensor probes for
my fishtank, does anyone know where I can get hold of some?

RS Components sell it.

http://rswww.com

You may find that some long stainless steel bolts fitted to a block of
plastic would be a less expensive alternative.

For this application, go for 316 or A4 spec. which is food grade.



..andy

To email, substitute .nospam with .gl

Andy Hall wrote:
On Thu, 22 Jul 2004 10:15:10 +0000 (UTC), "Lawrence Zarb"
wrote:

I need some stainless steel rods to act as water level sensor probes for
my fishtank, does anyone know where I can get hold of some?

RS Components sell it.

http://rswww.com

You may find that some long stainless steel bolts fitted to a block of
plastic would be a less expensive alternative.

Screwfix sell stainless studding in 1 metre lengths.

--
Chris Green

I need some stainless steel rods to act as water level sensor probes for
my fishtank, does anyone know where I can get hold of some?


welding supply stores. ask for ss tig rods. they come in various dia.

"Lawrence Zarb" wrote in message
news:2adb575602b51bc8772eb69234c20bea.52329@mygate .mailgate.org...
I need some stainless steel rods to act as water level sensor probes for
my fishtank, does anyone know where I can get hold of some?


Keep in mind, stainless is not really stainless. They will eventually
oxidize and rust. Just not as quick.

"Dan J.S." wrote in message
...

"Lawrence Zarb" wrote in message
news:2adb575602b51bc8772eb69234c20bea.52329@mygate .mailgate.org...
I need some stainless steel rods to act as water level sensor probes for
my fishtank, does anyone know where I can get hold of some?


Keep in mind, stainless is not really stainless. They will eventually
oxidize and rust. Just not as quick.



I think titanium will hold out longer in water. Also look into float
swit , hey are usually better for aquarium use. I'm assuming you will
be doing some kind of connectivity measurement to see if electricity can
flow between two rods, right? If it can, then water is touching it.
However, this would mean you would have electrical currents in the water,
which might affect your fish badly.

Harry

Harry,

It will be used to connect to a water alarm circuit which in turn is
connected to a water solenoid.
When I do my 20% water changes I have plumbed in a system that, via
carbon/water filters will fill up the tank directly from the mains by
opening a stopcock. the solenoid is there to stop the water when it
reaches a certain level (governed by the height of the rods) which shut
the water off, just in case I forget to turn the tap off. This is
because the water flow will be quite slow and it will take some time and
I donot want to be wating for the tank to fill up..


--
Posted via Mailgate.ORG Server - http://www.Mailgate.ORG

On Thu, 22 Jul 2004 12:56:26 GMT, wrote:



I need some stainless steel rods to act as water level sensor probes for
my fishtank, does anyone know where I can get hold of some?


welding supply stores. ask for ss tig rods. they come in various dia.

If this is not A4 food grade, then it is not appropriate for an
environment with fish. Some species are very sensitive to metals,
especially marine fish and invertebrates, alnthough some freshwater
species are as well.





..andy

To email, substitute .nospam with .gl

On Thu, 22 Jul 2004 14:02:46 +0000 (UTC), "Lawrence Zarb"
wrote:

Harry,

It will be used to connect to a water alarm circuit which in turn is
connected to a water solenoid.
When I do my 20% water changes I have plumbed in a system that, via
carbon/water filters will fill up the tank directly from the mains by
opening a stopcock. the solenoid is there to stop the water when it
reaches a certain level (governed by the height of the rods) which shut
the water off, just in case I forget to turn the tap off. This is
because the water flow will be quite slow and it will take some time and
I donot want to be wating for the tank to fill up..

One important point, Lawrence, is to make sure that one side of the
alarm sensor is connected to earth. Provided that you then have a
very high impedance sensor input on the alarm circuit, it won't be a
problem for the fish.

Another option, which I have used is to use a plastic float switch
fitted to a plastic bracket. These are almost as accurate as
contact arrangements and have the advantage that there are no metallic
items in contact with the water at all.

RS Components part number 228-1986 is suitable and pretty cheap.
I've recently used one of these in a water container which has a pump
to provide misting for my snake vivarium. I wanted an arrangement
that would stop the pump running if the container water level falls
too low - I don't want the pump running dry. THe pump is normally
turned on by a humidity sensor in the vivarium, but if the container
water level is too low a beeper sounds instead to remind me to fill
the container.

This application is not vastly different to yours in terms of what is
needed,




..andy

To email, substitute .nospam with .gl

Andy,
I have a float switch (a much easier solution) but it is just too big..


--
Posted via Mailgate.ORG Server - http://www.Mailgate.ORG

In message lgate.org,
Lawrence Zarb writes
I need some stainless steel rods to act as water level sensor probes for
my fishtank, does anyone know where I can get hold of some?


Why do you want to use stainless steel rods, and how?

Are you going to pass a current through them ?

Why not get a water level sensor - CPC sell them at a reasonable price
(about 7 quid IIRC)
--
geoff

In message lgate.org,
Lawrence Zarb writes
I need some stainless steel rods to act as water level sensor probes for
my fishtank, does anyone know where I can get hold of some?


Try a local radio dealer that sells "walkie talkie" type radios, most of
the whip aerials are stainless and there are always off cuts from when
they are cut/tuned to length. If you want a few bits drop me a line and
I'll put some in the post to you. What sort of voltage is going to be
between the probes? I have no idea what the fish could sense, but it may
be a consideration.
--
Bill

On Thu, 22 Jul 2004 10:15:10 +0000 (UTC), "Lawrence Zarb"
wrote:

I need some stainless steel rods to act as water level sensor probes for
my fishtank, does anyone know where I can get hold of some?


Bicycle spokes. Many are made of stainless steel, 0others of
titanium, probably lots of other materials. Got a bike shop near you?

For materials, these folks have almost everything:

http://www.mcmaster.com/


--

- Charles
-
-does not play well with others

It is amazing what people will invest/waste their time on.

"Charles" wrote in message
...
On Thu, 22 Jul 2004 10:15:10 +0000 (UTC), "Lawrence Zarb"
wrote:

I need some stainless steel rods to act as water level sensor probes for
my fishtank, does anyone know where I can get hold of some?


Bicycle spokes. Many are made of stainless steel, 0others of
titanium, probably lots of other materials. Got a bike shop near you?

For materials, these folks have almost everything:

http://www.mcmaster.com/


--

- Charles
-
-does not play well with others

"luminos" wrote in message
...
It is amazing what people will invest/waste their time on.

Or you could probably rig up a moisture sensor from an old PC expansion
card. The edge connectors are gold-plated.

Keith J.

Some people even fill glass boxes full of water and put fish in them...

"luminos" wrote in message
...
It is amazing what people will invest/waste their time on.

On Fri, 23 Jul 2004 02:46:31 -0500, "Limnophile"
wrote:


"luminos" wrote in message
...
It is amazing what people will invest/waste their time on.

Or you could probably rig up a moisture sensor from an old PC expansion
card. The edge connectors are gold-plated.

Keith J.



This is probably not suitable for use in an aqaurium as a result of
corrosion, which is why I suggested food grade stainless steel which
will withstand this.

Bear in mind that fish are very sensitive to metals.




..andy

To email, substitute .nospam with .gl

In article ,
Harry Muscle wrote:
I think titanium will hold out longer in water. Also look into float
swit , hey are usually better for aquarium use. I'm assuming you
will be doing some kind of connectivity measurement to see if
electricity can flow between two rods, right? If it can, then water is
touching it. However, this would mean you would have electrical currents
in the water, which might affect your fish badly.

Might be easier to run an IR beam across the tank?

--
*I couldn't repair your brakes, so I made your horn louder *

Dave Plowman London SW
To e-mail, change noise into sound.

On Thu, 22 Jul 2004 14:02:46 +0000 (UTC), "Lawrence Zarb"
wrote:

Harry,

It will be used to connect to a water alarm circuit which in turn is
connected to a water solenoid.
When I do my 20% water changes I have plumbed in a system that, via
carbon/water filters will fill up the tank directly from the mains by
opening a stopcock. the solenoid is there to stop the water when it
reaches a certain level (governed by the height of the rods) which shut
the water off, just in case I forget to turn the tap off. This is
because the water flow will be quite slow and it will take some time and
I donot want to be wating for the tank to fill up..


I use a mechanical float valve ( the type you find on humidifiers ) to
fill my storage tanks. You could probably modify a braket to fit on
the back of your aquarium to hold this in place. The only drawback is
that you will see a part of the float at the top of your water. Also
place a shut-off valve in line with your assembly.

have fun.

Bear in mind that fish are very sensitive to metals.
.andy

And sensitive to electricity?
Even a few millivolts?
I've heard of electric fishing lures and/or methods of 'attracting" (or
driving) pond fish towards electrodes placed in the water!
And none of these involve 'shocking' the fish into insensibility?

On Sun, 25 Jul 2004 12:00:44 -0230, "Terry"
wrote:


Bear in mind that fish are very sensitive to metals.
.andy

And sensitive to electricity?
Even a few millivolts?
I've heard of electric fishing lures and/or methods of 'attracting" (or
driving) pond fish towards electrodes placed in the water!
And none of these involve 'shocking' the fish into insensibility?




Yes they can be, Terry. Marine fish and certain species of
freshwater fish can become unwell in the presence of electric
currents. Hence, my earlier suggestion of making sure that any
sensing electronics is very high impedance.


..andy

To email, substitute .nospam with .gl

Bill wrote:

Try a local radio dealer that sells "walkie talkie" type radios, most of
the whip aerials are stainless

Careful! Often nickel-plated brass is used. I would not want them in my
tank.

If I had to build such a sensor, I'd probably use pencil mines (carbon
and clay in various proportions), as they are quite inert. You can buy
them from an office supply store in various diameters from 0.1 to 1 mm.

One other thing to keep in mind. If such electrodes are supplied with a
DC voltage, hydrolysis of water covers them with with gas bubbles, which
act as insulator. This process is called polarisation. To avoid the
effect, a low AC voltage should be used.

I know this may be getting too complex, but you could use a small tube, with
a guide of some sort, styrofoam ball and some sort of plastic "flap" that
would break an infrared beam to let you know that a certain level has been
reached...

I used that in a portable air conditioner to trigger a small timer circuit
to pump the water out of the unit, rather than keep emptying the unit in the
middle of the night.

I missed the top of the thread so I am adding my 2 cents worth now

Des.


"Dr Engelbert Buxbaum" wrote in message
...
Bill wrote:

Try a local radio dealer that sells "walkie talkie" type radios, most of
the whip aerials are stainless

Careful! Often nickel-plated brass is used. I would not want them in my
tank.

If I had to build such a sensor, I'd probably use pencil mines (carbon
and clay in various proportions), as they are quite inert. You can buy
them from an office supply store in various diameters from 0.1 to 1 mm.

One other thing to keep in mind. If such electrodes are supplied with a
DC voltage, hydrolysis of water covers them with with gas bubbles, which
act as insulator. This process is called polarisation. To avoid the
effect, a low AC voltage should be used.

"Desmond Wong" wrote in message
...
I know this may be getting too complex, but you could use a small tube,
with
a guide of some sort, styrofoam ball and some sort of plastic "flap" that
would break an infrared beam to let you know that a certain level has been
reached...

I used that in a portable air conditioner to trigger a small timer circuit
to pump the water out of the unit, rather than keep emptying the unit in
the
middle of the night.

I missed the top of the thread so I am adding my 2 cents worth now

Des.



How about just a standard float switch? Ready made, and it's designed
exactly for what the OP wants.

Harry