Do I need to mechanically filter the water before entering a sand filter? I am likely going to be using beads in side rather than sand. This is a fluid bed filter that can handle 100#'s of sand.
Fluidized sand filter
- Thread starter tank125
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It would be a very good idea. I use a sand bed for polishing water and reducing nitrates (yes, I actually want to convert nitrate to nitrite!).
If your flow rate through the filter is sufficient to give you a long entrainment column of sand and turbulent flow then a certain amount of abbrasion and mechanical breakdown of detritus will happen in your fluidized bed but you will be sending a lot of that back to your tank as BOD.
Mechanically active beds, if the energy level is too high have a tendency to 'eat' themselves through attrition and corrasion.
Interesting that you want to use beads instead of sand. Are these a type of bead that will support bacteria colonies on their surface?
If your flow rate through the filter is sufficient to give you a long entrainment column of sand and turbulent flow then a certain amount of abbrasion and mechanical breakdown of detritus will happen in your fluidized bed but you will be sending a lot of that back to your tank as BOD.
Mechanically active beds, if the energy level is too high have a tendency to 'eat' themselves through attrition and corrasion.
Interesting that you want to use beads instead of sand. Are these a type of bead that will support bacteria colonies on their surface?
I think beads is the wrong term, they are called "bio-barrels." I happen to have about 6 cubic feet of them that I got for free. I was thinking of using them instead of sand b/c their surface area is huge and they are light weight and will take a lot less pressure to fluidize as opposed to sand. My other option is buying the smallest one of these:
The LSB2.5
http://www.aquaticeco.com/subcategories/2652/Low-Space-Bioreactor-by-Clearwater
The LSB2.5
http://www.aquaticeco.com/subcategories/2652/Low-Space-Bioreactor-by-Clearwater
Interesting.
Rather than submerge the media and aerate the water I think a shower would be more effective. This gives you a much higher amount of available oxygen for the nitrobacter. Water saturates at aproximately 20 ppm dissolved oxygen, say 0.02 % by volume. By contrast, the atmosphere is roughly 20 % oxygen by volume a differance of a thousand times more oxygen!
A length of 15" sewer pipe will have an internal volume of 1.25 cubic feet per linear foot. A six foot length of it would hold your media with room to spare. At the top, screw on a flange with two penetrations; one for a vent and the other for your tank water. You will need to filter at least to the .5 mm particle size. Nipple through the flange and attach a cheap shower head to douse the stacked media. At the bottom bolt and seal a flange.
Drill and tap the 15" pipe side wall three or four inches from the bottom and install a return line back to your sump/tank. six inches above your drain, drill and tap another hole for a 1/4" pipe entrance. Plumb this line back to an air pump or your fish room blower. This is required to replenish the atmosphere inside the reactor as the nitrobacter consume the oxygen.
I would advise that the vent be plumbed to your house DWV venting system to limit the amouint of added humidity to your home from this filter. Air coming out of it will be saturated with moisture and could cause your windows to fog up in colder weather.
If your running at less than 10 gallons per minute, this will be a very effective and low cost reactor for you.
Rather than submerge the media and aerate the water I think a shower would be more effective. This gives you a much higher amount of available oxygen for the nitrobacter. Water saturates at aproximately 20 ppm dissolved oxygen, say 0.02 % by volume. By contrast, the atmosphere is roughly 20 % oxygen by volume a differance of a thousand times more oxygen!
A length of 15" sewer pipe will have an internal volume of 1.25 cubic feet per linear foot. A six foot length of it would hold your media with room to spare. At the top, screw on a flange with two penetrations; one for a vent and the other for your tank water. You will need to filter at least to the .5 mm particle size. Nipple through the flange and attach a cheap shower head to douse the stacked media. At the bottom bolt and seal a flange.
Drill and tap the 15" pipe side wall three or four inches from the bottom and install a return line back to your sump/tank. six inches above your drain, drill and tap another hole for a 1/4" pipe entrance. Plumb this line back to an air pump or your fish room blower. This is required to replenish the atmosphere inside the reactor as the nitrobacter consume the oxygen.
I would advise that the vent be plumbed to your house DWV venting system to limit the amouint of added humidity to your home from this filter. Air coming out of it will be saturated with moisture and could cause your windows to fog up in colder weather.
If your running at less than 10 gallons per minute, this will be a very effective and low cost reactor for you.
so you don't like the low space bioreactors by aquatic eco? As far as building what you described, I don't need to because I have a half dozen unused bio-towers that I could use. I am just looking for the most efficient filter. Big tanks/systems seem to always use fluidized sand filters, I would think that the LSB is the next generation.
Biotower refers to a number of things, so I'm not sure what you meen. Are they any one of these;
http://www.microsweep.com/uploads/BioTower_701-O3.pdf
http://www.biosystemsolutions.com/solutions/biotower.html
http://shop.microsweep.com/product.sc;jsessionid=20D71B49F5D4C3BA67550BF314F8E59A.qscstrfrnt03?productId=1
http://www.chemrec.co.uk/News/news.asp?yr=2001&mth=November
etc,
I suspect you mean something like:
http://www.thekrib.com/Filters/Sasala/wet-dry.html or a wetdry filtration system. If that is the case then it would have similar performance characteristics than the method I describe although it is important to provide a dark atmosphere for nitrobactor to prevent competition from algae, which can also affect the pH of the reactor stream. The system you are looking at I suspect is in essence a giant wet/dry filter.
Fluidized filters have tremendous surface area because the ratio of surface area to volume increases as the particle size decreases. Fine sand filter beds when fluidized have surface area measured in square kilometers for what seems like a small amount of material.
You can't expect to load one with bioballs and get the same effect since you won't have as much surface area for the bacteria to colonize.
http://www.microsweep.com/uploads/BioTower_701-O3.pdf
http://www.biosystemsolutions.com/solutions/biotower.html
http://shop.microsweep.com/product.sc;jsessionid=20D71B49F5D4C3BA67550BF314F8E59A.qscstrfrnt03?productId=1
http://www.chemrec.co.uk/News/news.asp?yr=2001&mth=November
etc,
I suspect you mean something like:
http://www.thekrib.com/Filters/Sasala/wet-dry.html or a wetdry filtration system. If that is the case then it would have similar performance characteristics than the method I describe although it is important to provide a dark atmosphere for nitrobactor to prevent competition from algae, which can also affect the pH of the reactor stream. The system you are looking at I suspect is in essence a giant wet/dry filter.
Fluidized filters have tremendous surface area because the ratio of surface area to volume increases as the particle size decreases. Fine sand filter beds when fluidized have surface area measured in square kilometers for what seems like a small amount of material.
You can't expect to load one with bioballs and get the same effect since you won't have as much surface area for the bacteria to colonize.
Darn it, bio barrel was the wrong word, these things are like 1/2" by 1/2" and are light weight plastic. LSB's suspend the material in water. you need a pump to flow water through, the air pump suspends the media, much like a high pressure water pump suspends the sand in an FSB. Info from Aquatic Eco site:
Low Space Bioreactor by Clearwater™
Fully automatic, self-adjusting and continuously self-cleaning!
There are many types of biofilters used in aquaculture, including trickling, submerged, rotating biological contactors (RBC) and fluidized beds. AES has introduced the revolutionary Clearwater™ Low-Space Bioreactor (LSB). While other biofilters manage an average of 3 kilograms of feed per cubic meter of biofilter volume per day, the LSB manages as much as 12 kilograms of feed per cubic meter. That's 440 grams of total ammonia-nitrogen (TAN) per cubic meter of media per day. Our smallest LSB will handle a standing stock of fish up to 140 pounds.
This is a robust, nonpressurized biofilter that is much less sensitive to flowrate variations and power interruptions than fluidized bed sand biofilters. When operated in low-head recirculating systems, it can easily be sunk into the floor to reduce the pump pressure. When installed this way, only a few inches of head loss will occur across the LSB. Because air is used to circulate the media, the LSB both adds oxygen and strips carbon dioxide! A hood can be placed over the bioreactor to vent the CO2 outdoors. We have colored them blue/green to prevent algae growth inside and provide the dark environment preferred by the Nitrobacter bacteria.
Air diffuser depth can be adjusted for compatibility with your blower/compressor. The LSBs are complete with media. Compressed air connections are 1/2" slip. Air pump not included. All you need are male-threaded pipe connections. We can also custom-build larger sizes.
***by bio tower I meant this:
Low Space Bioreactor by Clearwater™
Fully automatic, self-adjusting and continuously self-cleaning!
There are many types of biofilters used in aquaculture, including trickling, submerged, rotating biological contactors (RBC) and fluidized beds. AES has introduced the revolutionary Clearwater™ Low-Space Bioreactor (LSB). While other biofilters manage an average of 3 kilograms of feed per cubic meter of biofilter volume per day, the LSB manages as much as 12 kilograms of feed per cubic meter. That's 440 grams of total ammonia-nitrogen (TAN) per cubic meter of media per day. Our smallest LSB will handle a standing stock of fish up to 140 pounds.
This is a robust, nonpressurized biofilter that is much less sensitive to flowrate variations and power interruptions than fluidized bed sand biofilters. When operated in low-head recirculating systems, it can easily be sunk into the floor to reduce the pump pressure. When installed this way, only a few inches of head loss will occur across the LSB. Because air is used to circulate the media, the LSB both adds oxygen and strips carbon dioxide! A hood can be placed over the bioreactor to vent the CO2 outdoors. We have colored them blue/green to prevent algae growth inside and provide the dark environment preferred by the Nitrobacter bacteria.
Air diffuser depth can be adjusted for compatibility with your blower/compressor. The LSBs are complete with media. Compressed air connections are 1/2" slip. Air pump not included. All you need are male-threaded pipe connections. We can also custom-build larger sizes.
***by bio tower I meant this:
I like this unit and the operating concept but I have a couple of concerns;
GL and post pics once you set up.
- It would appear the blower required to operate the unit would be quite substantial but nowhere was I able to find the required ratings. I note that the blower is not included with the unit.
- One of the operating principles the unit relies upon is maintaining a thin bacterial film on the media in order to ensure maximum BB efficiency. It claims to do this by media collisions and turbulent flow in the reactor. In nature thin films are maintained by predation from protists and larval copepods as well as grazing by snails and other detritovores. I personally use snails in my cannisters to acheive this. If the films are 'knocked off' rather than eaten, what happens to them? Presumably they would be flushed out of the filter and back into your system.
GL and post pics once you set up.
Well I happen to have the air pump already, but if you feel that regular bioball towers are just as good assuming they are kept in the dark, I will just use what I have already.
tank125;2614898; said:
To answer the question, yes and a filter sock or two will work if cleaned regularly.
What type of container will you be using and what kind of volume are you considering?
Bio-Towers and Bio_filters and circulating Bio-media (either media or cage) all react similarly. One member on here used cut up beverage straws for his media. I've used shotgun wadding plus most of the other commercial bio-ball types of material for all three types of systems.
Sand of course has the highest surface area per volume.
You may be interested in Bio-film wheels too.
Dr Joe
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