Led Setup

[davepencilguin]

I was thinking about setting up my new 20 gallon tank with clear gravel, and running underneath would be a string of colored LEDs.
The only problem I see is the electric current to power the lights harming my fish.

Would a current of about 3 volts harm them or should I try and completely isolate the electricity from the water?






Any ideas?

 

[guppy_man]

Completely isolate the electricity from the water

 

[Rooster]

Clear gravel ? then why not just light it from OUTSIDE the tank ! (ie from below)

 

[davepencilguin]

I can't seem to find clear gravel anywhere

I was thinking covering any wire or LED exposed with silicone caulk.
That way it'd be isolated from the water.

But would the silicone be harmful?

 

[Rooster]

I can't seem to find clear gravel anywhere

I was thinking covering any wire or LED exposed with silicone caulk.
That way it'd be isolated from the water.

But would the silicone be harmful?

NO... but it wold be messy ! How about putting the lot onto a single clear tube, most garden centres/aquatic centres stock various sizes.

As for clear gravel, Ive often eyed up the pile of "gravel" next to a smashed up bus stop, and wondered..... ;-)

 

[8inary]

I understand what you are trying to achieve, however if the electronics are not completey isolated, then you will be putting/creating electrolysis in the water, which is a big no no for your fish.

And Rooster lol, I think that stuff is also quite cheap!

 

[KraKen]

I understand what you are trying to achieve, however if the electronics are not completey isolated, then you will be putting/creating electrolysis in the water, which is a big no no for your fish.

What's so bad about it? I aways thought that it would be an interesting expiriment to see what the effects of injecting pure oxygen into a tank via electrolysis. Also electrolysis was succesfully used to promote coral growth in the ocean.

As far as waterproofing the electronics go you could try spray on acrylic.

 

[Lateral Line]

How do you propose to introduce pure O2 into the tank and to what end? As for promoting coral growth in the ocean with electrolysis, could you provide a link to an acredited source?

 

[Wolfenrook]

Pure O2 is highly flammable and explosive, and shouldn't be played with. As to 'electrolysis' in a tank, O2 given off wouldn't be a big problem, but the electrical current would mess with the nervous systems of the livestock, and metal ions released would most likely be toxic, not to mention that if you are thinking of splitting the hydrogen and oxygen this would lead to the release of +ve charged hydrogen ions lowering the pH dramaticly, as well as hydrogen gass which is also flammable and explosive and even worst when mixed with pure oxygen....

Electricity and water are not a toy to be played with, another vote for 'isolate the current from the water' here, easily done by just making sure that any exposed cabling etc is kept well away from anywhere that water or humidity can get at it. You could I suppose seal your leds inside none toxic resin once the cable was attached to the base of the LED, or use a water proof housing with all entry points sealed with aquarium silicon.

Alternatively, don't DIY it and purchase a purpose built unit such as one of the hydor ones, they're not exactly expensive.

Ade

PS. Passing an electrical current though an open system such as an ocean is a very different proposition from doing the same in a small closed system such as a home aquarium. The experiment Kra is refering to is documented here.

 

[Rooster]

NO NO NO NO NO... never and thats NEVER allow an electrical current "loose" in an aquarium, water has 2 components - Oxygen and hydrogen, and theres twice as much hydrogen as oxygen, as in H2 O !!!!!
As far as I know, theres not a living thing that can breath hydrogen.

Chemistry aside, all fish use electrical sensors which can detect miniscule electrical charges (or rather changes) and introducing what amounts to a MASSIVE current (comparitivly) into the water will disorient fish, or worse.

Electrolosis uses DC, which is worst of all... as not only will it liberate O2 and H, but also metals/minerals will migrate from the terminals... not good.

 

[KraKen]

I hadn't thought of the metal ions released from the electrodes or how the current would mess with the fish's nervous system, so I guess that wouldn't work.

However the oxygen and hydrogen gasses released would be harmless. This is the water electrolysis reaction, 2H2O + electricity => 2H2 + 2O2

As you can see the hydrogen produced is in the form of hydrogen gas, not hydrogen ions, so the pH wouldn't be affected. Since we would use at most 9 volts for this reaction it wouldn't produce enough hydrogen and oxygen to produce any kind of signifigant explosion, nor would you want to collect the hydrogen in the first place(unless you're a pyromaniac or are lucky enough to have a hydrogen powered car). The biggest danger involved in electrolysis is producing chlorine gas but since we're dealing with freshwater and low voltages that wouldn't be a problem

I've heard of people injecting pressurised oxygen into thier tanks like you would CO2, I figured that a safer and easier way to do this would be electrolysis but since thios would mess with the fish's nervous system and release metal ions a better way would be to electrolysise a seperate container of watere and have a tube going from the electrode generateing oxygen to the tank.

 

[andywg]

How do you propose to introduce pure O2 into the tank and to what end? As for promoting coral growth in the ocean with electrolysis, could you provide a link to an acredited source?

A link has already been posted, but I did draw attention to passing electricity through a reef rack some time ago in this thread.

On the subject of electricity in tanks, an interesting read is found here. It's not quite entirely on topic to the OP's idea, but is intriguing.