Fluidized Bed Filter

Hey Peter. A small sand/silica would be good. One that is easily suspended in water. Prof, Would it not be possible to add a battery powered air pump id the power were to fail?

 

Hi Firefly,

Yes, it would certainly be OK if you had a battery powered air pump if the power failed, but are you going to be at home when the power fails to switch it on?

Kind regards,

Dirk

 

that idea may work firefly, if you could trigger the battery power to switch on with a relay the same way that a ups powers on when the ac is cut

 

there is a air pump on the market with built in battery backup and switches to battery power automatically.

something like this http://www.americanaquariumproducts.com/NonStopAirPump.html

 

Got all you guys loud and clear. So we can add the fluidized bed filter to our tanks just as long as we have a internal filter running. So I'm guessing that if the power does fail you still have the internal filter or canister to fall back on!

 

If the power fails and, filters and pumps will also fail......

 

Okay well here we go,the filter can work fine if used with floating or semi floating media.and since its floating it should overcome the lack of oxygen(suffocation of bacteria) for your bacteria reason that the media will be at the top of the water.that's if it aint a sealed system

 

He is trying to say.....

If the Power head to the bed filter fails, the internal filter will perform as a Backup and keep filtration going. If the overall Main power gets stuffed....you should have an auxiliary power supply that activates when the mains go out.

If you can make a switch between your mains, power supply and your filters that keeps the main power running only when power goes through it this should switch to the power supply once the power goes out with little delay. It would probably have to be a spring loaded switch run on a motor.

I will get some diagrams up to clarify my thoughts...

:idea:

Please see pic before reading this part.........

The main power runs the motor...hence the reason for a Step down transformer. The motor turns in one direction and touches the points and applies a constant touch and bridges the current from the mains to your filter. This is when the electricity in your home is working fine.

When the mains is cut off, the shaft springs back into its original position and touches the points where the current is coming from your power supply. Now the motor is off and the shaft now bridges the current from the battery to the filter.

You don't have to be there to switch your power supply on. The spring does the switching for you. Both outlet currents go through a step up transformer and can be run as a normal Plug point.

I forgot to mention that the motor system plugs into an existing wall socket ... this is therefore referred to as the 'Main Power'

Any Comments?

 

This is the reason why if your power fails, why your canister filter etc still work afterwards. So a back up power source is not that important, although it is extremely important, if the fluidized bed filter is your only form of filtration.

 

You can always consider my idea above and take the design to an electrical engineer if the bed filter is the only form of filtration.

 

Hi Guys

I was thinking about what Proff was saying about the sand being heavy and when the power goes off the it becomes compact so the BB then starts to die. So what if we used bio balls instead of the sand. You could use about 20-30 small bio balls they will still move around but the surface area would not be they same.

 

The thing that separates a FBF from a canister filter with BIO BALLS is that the particles are always moving. When the particles collide, they rub off some of the bacteria leaving place for more to grow. That is why bio balls would not be a smart move.

 

Hi Peter,

Yes, your deductions are correct, however, the longer the power is off the greater the chance is that the bacteria in the filter will die. If the power is off for more than 8 hours bacteria in power filters will also die off, so then the emergency power supply becomes a major issue.

In my recirculating discus setup I run a trickle filter. This filter has a spray bar that sprays the aquarium water over a gravel bed and then the bacteria on this gravel bed do the biological filtration. When the power goes off, all the water runs OUT of this filter and is then replaced by air. The gravel bed is however still enclosed basically in an aquarium so that it cannot dry out. If you were to have a power fail with this filter, the bacteria will not get damaged even if the power is off for 24 hours, I have carefully tested this.

Tankmaster, Peter is a grade 10 learner so his budget is a little limited..... he still has to become the accountant or doctor before he can afford this sort of thing!

Rockerickc, the advantage with a fluidized bed filter lies in the fact that you use the sand which has the large surface area. As soon as you use bioballs there is no surface advantage any more and then you could just as well go back to your canister filter.

So bottom line is that power failures cancel out the advantages of fluidized bed filters unless you have an emergency power supply.

Kind regards,

Dirk

 

Understood Prof

Great filter you have there. Trickle filters are also a great idea, only problem is that you need a sump on your tank.

 

Hi Prof, thanks for the clarification. Perhaps this is a bit off topic, but could you please post a photo of how your trickle filter with the gravel bed looks? I've been having quite a few power outages lately and I think I need to look into something like that.

As for the FBF, it sounds like an interesting concept, but it looks like you'll really need a sump to be able to use it effectively. Unless you can make a Hang-on mount that incorporates the pump and most likely a sponge to cover the intake.

 

Hi Roderickc and Whipme,

perhaps you should start a new thread about trickle filters and then we can get to discussing them separately from this thread.

Kind regards,

Dirk

 

Hi prof, does it have to be fine sand. I saw a "youtube" vid/s about them using "K1 filter media" as a fluidised bed filter. Do you think this would work? Most of these one's rely on an air pump as a power source.

 

The principle of these filters is that the finer the sand is, the greater the surface area will be. Coarser sand will not have as large a surface area and therefore will not be as efficient. However, this does not mean that such a filter will not work, it certainly will once the bacteria are established on the sand.

Kind regards,

Dirk

 

So if the idea is to get a large surface area - surely one could also consider perlite for both trickle and FBF ? Other than is being a pain to work with it should work AFAIK.

Later Ferdie

 

Ferdie,

As far as I know Perlite floats, so this cannot work?

Kind regards,

Dirk