Filter advice?
- Thread starter Mab
- Start date
Different types include undergravel (UGF), internal, and external. The external category can further be broken down by hang-on-back and canister. There is also an additional type of external filter called wet-dry or trickle filters.
There are also different tasks that are accomplished by different types of filtration. These include biological, mechanical, and chemical. Biological filtration is also refered to as bacterial cycling, where ammonia is oxidized into nitrItes and then further oxidized to yield nitrAtes. Mechanical filtration, as the name implies, is simply straining particulate material from the water. Chemical filtration makes use of acivation carbon, zeolite, peat, or synthetic resins to chemically alter the water composition.
With that out of the way, let's look at the basic filter types along with the pros and cons of each:
(1) Undergravel Filter (UGF) - This used to be the filter of choice when I started fishkeeping, but has fallen out of favor in the past decade or so. It is comprised of a perforated plate that rests on the aquarium bottom. A layer of gravel is placed on top and powerheads or airlifts are used to draw water down through the gravel and up through the uplift tubes and out to the aquarium. Fish wastes and excess food are drawn down into the bacteria-rich substrate where it is converted it to nitrItes, then nitrAtes. Works primarilly as a biological filter, but also serves as some mechanical filtration as the solids are drawn towards the substrate.
Pro: Simple to set up and operate.
Con: Tend to clog up with detritus. Excessive build-up of organics believed to be major contributor of "old tank syndrome" or otherwise unexplainable crashes. Not plant-friendly. Little or no chemical filtration options. Can create oxygen deprived conditions.
(2) Internal Filter - These are typically small boxes that are placed in the aquarium and utilize either an airlift (old-style - I'm not sure these are made any more) or small internal pump to draw water through the filter media. The media is usually comprised of a sponge for mechanical/biological filtration and there are often provisions for additional chemical media.
Pro: Inexpensive. Effective. Versatile. Often the filter of choice for raising or growing out fry.
Con: Often unattractive. Maintenance requires disturbing aquarium and its inhabitants.
(3a) External Hang-On-Back (HOB) Filter - These are probably the most popular filters for small to moderate sized tanks (75 gallon and less). Water in drawn through a siphon tube by a small self-contained pump and expelled through the filter media and then returned to the tank. The choices of filter media are almost limitless and include sponge for mechanical/biological filtration; activated carbon, peat, zeolite (ammo-chips), phosphate absorbing resins, and others for chemical filtration/treatment as desired. In addition, some filters such as the Marineland Penguin and Emeror models also include bio-wheels that add substantial bacteria colonizing potential in an oxygen-rich environment that is optimum for their well-being.
Pro: Relatively inexpensive (great bang for the buck). Extremely versatile. Easy maintenance. In addition, I have found HOB filters from reputable manufacturers to be very durable (I have a Hagen AquaClear 500 that is several years old and has been trouble-free).
Con: Sometimes noisy, although this is usually a waterfall noise that can often be remedied by topping off the aquarium. Require adequate space behind aquarium.
(3b) External Cannister Filter - Cannister filters pump water through an inlet tube, pass it through the selected media, and then return it to the tank by way of an outlet tube. These offer the same versatility as their HOB brethren. They are often employed in larger tanks (55 gallon and larger) and are usually housed in the stand.
Pro: Extremely versatile. Usually virtually silent operation. Design allows for selective placement of inlet and outlet tubes. Usually very durable. Fairly easy to maintain. Require very little clearance behind tank. Can be placed out-of-sight.
Con: Expensive. Tend to foul fairly quickly in cases of power outages.
(4) Wet-Dry or Trickle Filter - Water is drawn from the aquarium by an overflow box or similar arrangement and then trickles through a tower that contains plastic or ceramic media that encourages bacterial growth. The water then collects in a sump and is then pumped back to the aquarium. Chemical filtration media can be placed in the sump as desired. These are almost exclusively reserved for big tanks (in excess of 100 gallons).
Pro: Very efficient biological filtration. Versatile.
Con: Very expensive. Often noisy from the overflow box, the trickle tower, and/or the return pump. Complex and often problematic.
Now my questions for you:
Why do your fish give off a lot of waste? Is it because of overfeeding or overstocking?
What type and how many fish do you have?
There are also different tasks that are accomplished by different types of filtration. These include biological, mechanical, and chemical. Biological filtration is also refered to as bacterial cycling, where ammonia is oxidized into nitrItes and then further oxidized to yield nitrAtes. Mechanical filtration, as the name implies, is simply straining particulate material from the water. Chemical filtration makes use of acivation carbon, zeolite, peat, or synthetic resins to chemically alter the water composition.
With that out of the way, let's look at the basic filter types along with the pros and cons of each:
(1) Undergravel Filter (UGF) - This used to be the filter of choice when I started fishkeeping, but has fallen out of favor in the past decade or so. It is comprised of a perforated plate that rests on the aquarium bottom. A layer of gravel is placed on top and powerheads or airlifts are used to draw water down through the gravel and up through the uplift tubes and out to the aquarium. Fish wastes and excess food are drawn down into the bacteria-rich substrate where it is converted it to nitrItes, then nitrAtes. Works primarilly as a biological filter, but also serves as some mechanical filtration as the solids are drawn towards the substrate.
Pro: Simple to set up and operate.
Con: Tend to clog up with detritus. Excessive build-up of organics believed to be major contributor of "old tank syndrome" or otherwise unexplainable crashes. Not plant-friendly. Little or no chemical filtration options. Can create oxygen deprived conditions.
(2) Internal Filter - These are typically small boxes that are placed in the aquarium and utilize either an airlift (old-style - I'm not sure these are made any more) or small internal pump to draw water through the filter media. The media is usually comprised of a sponge for mechanical/biological filtration and there are often provisions for additional chemical media.
Pro: Inexpensive. Effective. Versatile. Often the filter of choice for raising or growing out fry.
Con: Often unattractive. Maintenance requires disturbing aquarium and its inhabitants.
(3a) External Hang-On-Back (HOB) Filter - These are probably the most popular filters for small to moderate sized tanks (75 gallon and less). Water in drawn through a siphon tube by a small self-contained pump and expelled through the filter media and then returned to the tank. The choices of filter media are almost limitless and include sponge for mechanical/biological filtration; activated carbon, peat, zeolite (ammo-chips), phosphate absorbing resins, and others for chemical filtration/treatment as desired. In addition, some filters such as the Marineland Penguin and Emeror models also include bio-wheels that add substantial bacteria colonizing potential in an oxygen-rich environment that is optimum for their well-being.
Pro: Relatively inexpensive (great bang for the buck). Extremely versatile. Easy maintenance. In addition, I have found HOB filters from reputable manufacturers to be very durable (I have a Hagen AquaClear 500 that is several years old and has been trouble-free).
Con: Sometimes noisy, although this is usually a waterfall noise that can often be remedied by topping off the aquarium. Require adequate space behind aquarium.
(3b) External Cannister Filter - Cannister filters pump water through an inlet tube, pass it through the selected media, and then return it to the tank by way of an outlet tube. These offer the same versatility as their HOB brethren. They are often employed in larger tanks (55 gallon and larger) and are usually housed in the stand.
Pro: Extremely versatile. Usually virtually silent operation. Design allows for selective placement of inlet and outlet tubes. Usually very durable. Fairly easy to maintain. Require very little clearance behind tank. Can be placed out-of-sight.
Con: Expensive. Tend to foul fairly quickly in cases of power outages.
(4) Wet-Dry or Trickle Filter - Water is drawn from the aquarium by an overflow box or similar arrangement and then trickles through a tower that contains plastic or ceramic media that encourages bacterial growth. The water then collects in a sump and is then pumped back to the aquarium. Chemical filtration media can be placed in the sump as desired. These are almost exclusively reserved for big tanks (in excess of 100 gallons).
Pro: Very efficient biological filtration. Versatile.
Con: Very expensive. Often noisy from the overflow box, the trickle tower, and/or the return pump. Complex and often problematic.
Now my questions for you:
Why do your fish give off a lot of waste? Is it because of overfeeding or overstocking?
What type and how many fish do you have?
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Thank you for the wonderful filtration info. The fiiltration right now is just to ease a bad situation but temporary situation. I have been looking for homes for the goldfish, koi and shark. i have found a home for the koi who is going to a local breeder who has a large and long established pond for when it gets big. the golfish may have a new 10g home to himself very soon with one of my friends. george is the problem, one because i am more worried about his health and two because no one wants a catfish who gets to be around 3 feet. Im hoping i can convince a fish store to take him but am worried i wont be able to find a home for him because hes sick or over fed. If u have any ideas please let me know.
The three balas (all of which are quite small), who i actualy inadvertantly and unwillingly aquired, im hoping to keep in the 30g tank with the placoscomus (spelling?) untill they get bigger and Ill move them to a 60 gallon tank which i have been saving for.
Do u think that this would work?
I didnt know much about filters before and i wanted to do my best not to cause any more damage. The only fish i actually bought were George and the goldfish. All i wanted was a goldfish and a small tank then my roomate begged me to get george. since then ive been kinda overwhemed with other peoples fish. The pet store gave me bad and innaccurate advice and I really have no idea what Im doing. I have more fish than i can handle or afford. Id really like to keep a tank that provides a healthy environment for a small number of fish. Any and all advice on how to get to this point is more than welcome.
The three balas (all of which are quite small), who i actualy inadvertantly and unwillingly aquired, im hoping to keep in the 30g tank with the placoscomus (spelling?) untill they get bigger and Ill move them to a 60 gallon tank which i have been saving for.
Do u think that this would work?
I didnt know much about filters before and i wanted to do my best not to cause any more damage. The only fish i actually bought were George and the goldfish. All i wanted was a goldfish and a small tank then my roomate begged me to get george. since then ive been kinda overwhemed with other peoples fish. The pet store gave me bad and innaccurate advice and I really have no idea what Im doing. I have more fish than i can handle or afford. Id really like to keep a tank that provides a healthy environment for a small number of fish. Any and all advice on how to get to this point is more than welcome.
I think everyone has all three to some extent in their tanks...maybe not so much the chemical side...but definitely the biological and mechanical....otherwise our tanks would all be cloudy and not support the fish 
Well written Turbine...thats exactly what I was going to suggest CFM! great minds think alike
It should also be said that different people have different thoughts on which types of filter work the best...and in all honesty for each application there is probably one type that would work the best, but that isn't the same for every application. Everything from the dimensions of the tank to the size of the tank to the bioload are things to consider.
btw...a huge sponge filter/box filter/internal filter is what my parents use on their outdoor ponds...so they're not only used in a bare bottom/fry tank situation.
Well written Turbine...thats exactly what I was going to suggest CFM! great minds think alike
It should also be said that different people have different thoughts on which types of filter work the best...and in all honesty for each application there is probably one type that would work the best, but that isn't the same for every application. Everything from the dimensions of the tank to the size of the tank to the bioload are things to consider.
btw...a huge sponge filter/box filter/internal filter is what my parents use on their outdoor ponds...so they're not only used in a bare bottom/fry tank situation.
You do need all three types of filtration, but that's easy.. I have a PennPlax 150 that contains 4 types of filtration-1) Polyfiber Floss Cartridges traps floating particulate matter. 2) Activated Carbon Cartridge removes harmful chemicals, toxins, odors, discoloration and other contaminants. 3) Internal Sponge optimizes colonization of beneficial aerobic bacteria that removes ammonia and nitrates. 4) External Bio-Falls is the wet/dry biological booster for addtiaional ammonia and nitrate removal. Bio-Falls also enhances the oxygen exchange for maximum water oxygenation.
And it's a relatively small filter. I also use the Emperor 280 on all three of my tanks, which does the same things. It's not hard to cover all the bases with filtration.
And it's a relatively small filter. I also use the Emperor 280 on all three of my tanks, which does the same things. It's not hard to cover all the bases with filtration.
