Fluidized sand bed filter
- Thread starter Franna29
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A fluidized sand bed filter does produce the first part of the Nitrogen cycle
They do produce the nitrates.
But that is released into the water column due to the design. And once nitrates are in the water column it is very hard to get them to nitrogen using bacteria. Because most of the bacteria sits on something and are not free swimming. They do support aerobic bacteria but not the anaerobic bacteria we need to complete the nitrogen cycle. Basically the same as bio-balls in a wet/dry filtration chamber.
Then also your setup must be right. Too strong a pump and you blow the sand all over. Or out of the reactor. Using mesh or filter wool to prevent the sand from going out, they just block up as well and stops all flow, killing all bacteria in a reactor body.
At some point there was a V shape design with sand tumbling around. Again, need to ensure the sand stays inside the V, and have enough movement to prevent dead areas.
Power goes out, and that great colony of aerobic bacteria starts to die out fast. Same with NP-pellet reactors.
They do produce the nitrates.
But that is released into the water column due to the design. And once nitrates are in the water column it is very hard to get them to nitrogen using bacteria. Because most of the bacteria sits on something and are not free swimming. They do support aerobic bacteria but not the anaerobic bacteria we need to complete the nitrogen cycle. Basically the same as bio-balls in a wet/dry filtration chamber.
Then also your setup must be right. Too strong a pump and you blow the sand all over. Or out of the reactor. Using mesh or filter wool to prevent the sand from going out, they just block up as well and stops all flow, killing all bacteria in a reactor body.
At some point there was a V shape design with sand tumbling around. Again, need to ensure the sand stays inside the V, and have enough movement to prevent dead areas.
Power goes out, and that great colony of aerobic bacteria starts to die out fast. Same with NP-pellet reactors.
Fluidized filters come in many configuration. Fluidized is not the same as Liquidized. Also fluidized does not have to be in in a liquid.
Fluidized substances include among others, Fluids, gases, plasma, and some plastic, silica, or many other solids.
The idea behind "Fluidized" filters is contact time. Put simply, bacteria has a bigger access area to media that is fluidized than media that is non fluidized.
Fluidized filters can be very efficient for performing a number of functions. In our hobby these can be fluidized calcium reactors, fluadised Phosphate filters, fluadised carbon reactors, fluadised (sand) aerobic filters, fluidized (sand) anaerobic filters, in fact just about any form of biological or chemical adsorption or absorption filter.
Getting back to the original question. I would first ascertain. What type of fluidized sand filter do you want to employ? and why?
Fluidized substances include among others, Fluids, gases, plasma, and some plastic, silica, or many other solids.
The idea behind "Fluidized" filters is contact time. Put simply, bacteria has a bigger access area to media that is fluidized than media that is non fluidized.
Fluidized filters can be very efficient for performing a number of functions. In our hobby these can be fluidized calcium reactors, fluadised Phosphate filters, fluadised carbon reactors, fluadised (sand) aerobic filters, fluidized (sand) anaerobic filters, in fact just about any form of biological or chemical adsorption or absorption filter.
Getting back to the original question. I would first ascertain. What type of fluidized sand filter do you want to employ? and why?
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please explain this to me?????????????????????????????? get facts straight for blurting stuff out like this
it is the most efficient way of NH4 and NO2 removal, Fluidized Bed Biological Filters are a small footprint/high surface area bio-filter. They use silica sand or garnet that offers a tremendous amount of surface area for colonizing "aerobic" bacteria. The Fluidized Bed Biofilter is more efficient at TAN (total ammonia nitrogen) removal than most other forms of aerobic filtration
his explanation is wrong, they work great and i use them all the time, i have made a DIY one and no issues... you can even put bio-pellets inside to help remove NO3, as there is no aerobic filter that removes NO3, besides bio-cubes or denitrators...
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use it for sand filter
I did not say they do not work. They work great, same as bio balls. But have their limitations. As already explained. 2 hours before being told
They work in essence the same as NP-Pellet reactors. Can be anaerobic , if tall enough.
But what happens if the power is out for 5 minutes? If these reactors are so great in being anaerobic, using a 1000L/h pump to pump in fresh new oxygen rich water, having enough bacteria to quickly use this available oxygen up so that the other anaerobic oxygen can do their bit. How quickly do they use the oxygen up when the pump stops flowing. Be that for a power outage or tank maintenance. How long can the aerobic bacteria last without new oxygen supply. And also the anaerobic, what happens with no flow after 10 minutes?
Fluidized filters are great. Look in the Koi industry at the Nexus filters with Kaldness media. Its great.
But why do they not use sand filters for Koi? Non-fluidized or swimming pool filters and the sand gets compacted, making tunnels and effectively just becomes tubes with water running through them. Fluidized, if you get the flow right, and have it on battery backup, yes, that could work. Even for Koi.
They work in essence the same as NP-Pellet reactors. Can be anaerobic , if tall enough.
I do not see this happening in the V shaped sump designs.
exactly the same as with a NP-Pellet reactor.
more flow, oxygen rich water entering or airstones should help. Getting the ratio right. Same issue with NP pellet reactor, to get the flow right.
But what happens if the power is out for 5 minutes? If these reactors are so great in being anaerobic, using a 1000L/h pump to pump in fresh new oxygen rich water, having enough bacteria to quickly use this available oxygen up so that the other anaerobic oxygen can do their bit. How quickly do they use the oxygen up when the pump stops flowing. Be that for a power outage or tank maintenance. How long can the aerobic bacteria last without new oxygen supply. And also the anaerobic, what happens with no flow after 10 minutes?
Fluidized filters are great. Look in the Koi industry at the Nexus filters with Kaldness media. Its great.
But why do they not use sand filters for Koi? Non-fluidized or swimming pool filters and the sand gets compacted, making tunnels and effectively just becomes tubes with water running through them. Fluidized, if you get the flow right, and have it on battery backup, yes, that could work. Even for Koi.
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a bit extra on koi and why not a swimming pool filter
Happy Koi - Happy Koi - Koi keeping done right!Sand filters
Happy Koi - Happy Koi - Koi keeping done right!Sand filters
Have you ever used one? It no more dangerous than a dsb, denitrator sulphur or not or pellets without elec. They actually work to well and of you don't have a nutrient export plan you can build up NO3 but with biocubes, pellets and vinegar not an issue
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I bit difficult to read, but more info on power outage
Question aslked and the replies from Bob in between marked in bold italic
Power Outage Bob, There was a power outage in my area last night. The good news is the power was only out for about an hour. The bad news is that I fell asleep prior to the power coming back on and the outage tripped the GFI's in my tank, so the tank power was out for about 6 hours.
...
My second question concerns my fluidized bed filter. When I first started setting my tank up last summer, I had originally planned on an all fish tank so I installed a fluidized bed filter on the sump. Instead, I've ended up with a flow blown reef tank (live rock, skimmer, many soft and stony corals and only 2 small fish). I've been considering shutting down the fluidized bed filter for some time now, <Yes, I would... just pull it> but since all water parameters were excellent, I figured why mess with a good thing. <May not be as "good a thing" as you can have> Well, I've read that the bacteria in fluidized bed filters can die very quickly if there is no flow through the bed (like I had for six hours last night!) <An hour is too long...> Well, I didn't want to blow all that dead stuff into my tank, so this morning when I restarted everything, I mad the decision to shut down the fluidized be filter. Do you think this was wise, or should I turn it back on. <You were wise, and fortunate to have done so> Sorry this was so long winded. By the way, the good news is that everything seemed to be doing fine this morning when I left for work...hopefully all will be well when I return this evening. <Yes> Thanks for you help, Phil in San Diego ...
FluidBedFAQs
Question aslked and the replies from Bob in between marked in bold italic
Power Outage Bob, There was a power outage in my area last night. The good news is the power was only out for about an hour. The bad news is that I fell asleep prior to the power coming back on and the outage tripped the GFI's in my tank, so the tank power was out for about 6 hours.
...
My second question concerns my fluidized bed filter. When I first started setting my tank up last summer, I had originally planned on an all fish tank so I installed a fluidized bed filter on the sump. Instead, I've ended up with a flow blown reef tank (live rock, skimmer, many soft and stony corals and only 2 small fish). I've been considering shutting down the fluidized bed filter for some time now, <Yes, I would... just pull it> but since all water parameters were excellent, I figured why mess with a good thing. <May not be as "good a thing" as you can have> Well, I've read that the bacteria in fluidized bed filters can die very quickly if there is no flow through the bed (like I had for six hours last night!) <An hour is too long...> Well, I didn't want to blow all that dead stuff into my tank, so this morning when I restarted everything, I mad the decision to shut down the fluidized be filter. Do you think this was wise, or should I turn it back on. <You were wise, and fortunate to have done so> Sorry this was so long winded. By the way, the good news is that everything seemed to be doing fine this morning when I left for work...hopefully all will be well when I return this evening. <Yes> Thanks for you help, Phil in San Diego ...
FluidBedFAQs
Nope.
But its a lot easier to keep slow flow over a DSB on a 3 day power outage than keeping a fluidized filter going. One less (big) pump.
And also, a lot better to use pre-filters on a fluidized filter, be that sand or carbon or whatever. No point in blocking the filter up with detritus.
Well my air pump and 80watt pump , 10000l per hour, works great keeping the flow through it, you actually want to post filter it and use the sand to grind the detritus down and feed etc. Google emporer aquatics sand filter. But this argument is moot it seems.
Back to the original poster, there is nothing wrong using a fsb filter as long as you understand the mechanics, this goes for most filtration solutions used in this hobby, eg zeovit , Berlin method
Cool thanx guys, this just goes to show. Different people have different views and opinions on reefkeeping,does in no case make anyone wrong or write, differet experiance makes for different opinoins. But thanx for both @RiaanP and @dallasg for your inputs, gives me a clear indication of probable pro's and cons so from this point onwards I can make a well informed choice in what direction to go. And hope this thred helps others in the same way in the future..
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