"Long story short i was given a couple 55 gallon tanks and would like to get them going for a month or two, to cycle before going back to the same tree and hopefully catching some more small panfish for the tank."
"I know that these fish would be messy eaters so i need help deciding what types of filters i need to be running. The only experience i have with larger filters are the back of the tank powerfilters. I know i am going to need much more than that this time."
Do you want the long or the short form of my response?
Short answer:
The easiest thing in the long term for you to do is a planted tank. The plants eat the waste and can reduce or completely eliminate water changes. If the fish aren't plant compatible and enjoy ripping them apart, you can easily link the water from the tank with the fish into a second tank that has the plants.
Long answer:
When fish food is added to the fish tank, whether or not it is eaten, the proteins in the fish food decay into ammonia/ammonium (they're in equilibrium). This ammonia/ammonium is toxic at even 0.25 and 0.5 parts per million. It has one nitrogen in it and either three or four hydrogens. There are two methods to removing this toxic compound from the water to prevent it from killing your fish.
1. Bacteria. Nitrosomonas bacteria convert ammonia to nitrite. Nitrite is one nitrogen with two oxygens instead of some hydrogens. It's still toxic but not as much as ammonia. Then nitrospira bacteria convert the nitrite into nitrate. This nitrate isn't toxic until on average 30 parts per million, depending on the fish species. Sunfish are on average way less sensitive to nitrate than cichlids. For example, while 30 ppm might wipe out a tank of Tanganyikans or discus, a tank of bluegill wouldn't even bat an eye at it. So. The frequency of water changes in your aquarium is based upon how quickly the nitrate accumulates and reaches that critical concentration above which your fish get sick. Things that increase the rate of accumulation are meaty foods (lots of protein with lots of nitrogen to decay into ammonia) and heavily stocked aquariums that require quite a lot of food quite frequently.
2. Plants. Plants eat both ammonium and nitrate when they are growing, and incorporate the nitrogen from those molecules into themselves to make their new leaves, stems, etc. Aquatic plants are different than terrestrial plants because they prefer ammonium over nitrate. They will switch from nitrate to ammonium whenever it is present and will remove it from the water in like four hours. Here is a website with a table and more information on it if you want more details about that:
http://www.theaquari...ical_Filtration Basically plants are awesome. They can either help out your bacterial filtration by removing nitrate and decreasing the frequency of your water changes, or they can be the base filtration themselves and directly remove ammonium from the water. If you have a plant in a tank and something terrible happens and there is an ammonia spike, the plants will remove that ammonia from the water within hours before you notice and before your surviving fish can be poisoned. A purely bacterially filtered tank doesn't have that ability, and could takes days (not hours) to respond to peaks in ammonia, meaning that more of your fish could die. The plant is a fail safe. It switches to eating the more toxic food when it's present, protecting your fish and really boosting your life support system. For that reason every tank, even if it is majority bacterially filtered, should contain at least one live plant. It's a fail safe. It'll remove ammonia in four hours instead of days/weeks.
So. Now that you've considered both options, plants may be starting to look like a good idea. How do we keep them alive? It turns out they're actually pretty easy to grow. They eat light, which is sort of neat. They don't eat green light. They prefer red and blue colored light. Because they're limited in which light they can eat, it's a good idea to get a 'full spectrum' bulb that produces the entire range of colors, that way no matter what colors your specific plant eats, they're being made by the light bulb. Not all white light bulbs make every color; white color can be made by a combination of other colors and you don't necessarily know what's in it. Therefore full spectrum is the way to go to be assured that no matter what color your plant needs, it's there. Personally I use the four foot long T8 fluorescent shop light from Home Depot ($20) or Walmart ($10), rest it right on the tank, and then put Daylight Deluxe bulbs in the fixture (they're $9 for two at Home Depot). Here are some pictures:
http://img.photobuck...imiru/013-2.jpghttp://img.photobuck...imiru/017-3.jpghttp://img.photobuck...imiru/014-4.jpghttp://img.photobuck...imiru/018-4.jpgNow that you've got lighting figured out, what do you use for a substrate (bottom stuff)? Well, you can either use a nutritious substrate that already had food minerals in it (iron, calcium, magnesium, etc) or you can use a barren substrate and then add fertilizer. Personally, I'm lazy, so I use a nutritious substrate so I don't have to fertilize it. For me, that's Special Kitty brand pure clay cat litter, no fragrances or clumping chemicals added. It's $4 for 25 pounds at Walmart. You can also use soil capped in gravel, or gravel/sand (pure silicon dioxide) with fertilizer sticks buried in it. Another alternative is to use floating or rootless plants, and then who cares what your substrate is or whether it's fertilized. I used to have a rectangle of half inch potable PVC pipe. The bottom half of the rectangle was buried under the substrate and the top half had ceratophyllum demersum (a rooted floating native plant) wrapped around it. You could barely even see the pipe, 'cause C. demersum is so fluffy. Also, it's a really fast grower. Great plant. I recommend it for people who fish rip apart other plants. It's spiky and hurts to touch, so they often leave it alone even when they destroy other plants.
http://img.photobuck...miru/mytank.jpgIf, after reading this, you still decide plants are stupid and you want just a filter and water changes like everybody else, well, that's fine. The most surface area (which bacteria grow on and colonize; more surface area is like more potential homes for them to move into) can be achieved with a fluidized bed filter. Here's a link with more information:
http://www.bioconlabs.com/abtqs.html They're cool. You can build one yourself for cheap with just a pump and a bag of sand and a container and a tube. Pump the water into the bottom of the container. At a high enough flow rate it'll push the sand up, 'fluidizing' it. The sand won't go all the way up to the top of the container. Let that clean, sand-free water flow into your tank. Cheap. Effective. Fluidized bed.
And, last thing, if you do get the tanks and decide to run them for a while before stocking them, just to let you know. If you do end up going with bacterial filtration only, add fish flakes to the tanks every day as if there were fish in it. The ammonia will serve as an initial food that will entice bacteria to move into the filter and colonize it. A tank set up waiting for fish won't get colonized if you don't feed it. There's a product by API called Quick Start that's about $20 and has live nitrosomonas and nitrospira bacteria if you'd rather pay $20 than wait a month. It's good stuff. Here's their science page:
http://cms.marsfishc...ience sheet.pdfIf you have plants you can add fish the same day; you don't need to wait weeks for bacteria to colonize it.
I just reread your post and see you that you said, "I realize 4 to 6 panfish in a 55 gallon tank is a bit crowded, but i will weed a couple of the fish out if need be after they grow a little." Don't release them back into the wild. They can carry invisible, no-symptom pathogens from the tank back into their home habitat. That's why even if it's a native fish, once you've taken it home (and exposed it to disease) don't release it back into the wild. There are lots of aquarium diseases like ich and mycobacterium marinum that we wouldn't want to see introduced into local waterways.
Also I know you didn't ask but in my personal opinion crappie are too large for a 55. You're in Iowa; why not get some nice native orangespotted sunfish? They're beautiful and they stay small.
Distribution:
http://nas2.er.usgs.... &speciesid=383Pictures of what they look like:
http://gallery.nanfa...e 2619.jpg.htmlhttp://gallery.nanfa...ageViewsIndex=1
Edited by EricaWieser, 23 November 2012 - 09:25 PM.