How much would you pay for an Eheim 2128 Pro II?

[J double R]

jcahow, thanks so much for the good reference! I don't think I'm ready for this sophisticated equipment yet. I still like my AC filters. Are these canister filters really that much better? Do they remove ammonia/nitrite/nitrate so that I can do less water changes?

Canister filters provide an exponentially higher amount of both physical and biological filtration. However, ANY filter is no substitute for water changes. A tank with proper filtration should have no ammonia or nitrites that need to be removed with water changes, and no filter will remove nitrates, only heavy planting and water changes.

Summary: Yes, canister filters (and specifically Eheim) ARE that much better, but there are NO substitutes for a proper cycle and water changes.

 

[jcahow]

You are incorrect, they are canister style filters containing specfiic bacteria that will remove just Nitrates. They all are very low flow volume filters because Nitrate removing bacteria want very little oxygen and need to be feed somehow (either with periodic injections or special dissolving feeding media).

Here is a link to one specfic brand that uses injections:

http://www.aquaripure.com/index.htm

Here is a long thread on the Australia Perth Cichlid forum disscussing a similar type Nitrate filter removing product (but a different brand using feeding media) because of tight water supplies in Sydney:

http://www.perthcichlid.com.au/forum/index.php?showtopic=25373

None of these brand recommends stopping water changes but many users go for far longer periods without having to do them due to low Nitrates forming in their tank with no apparent harm to their fish. Most minerals and elements fish need can be supplemented back to the tank manually if you are concerned.

Technology in the aqaurium world today allows for almost instant cycling (or at least must faster) and the removal of tank Nitrates. There is nothing wrong with traditional cycling and performing regular water changes but not everyone has the patience/ambition/time/cheap water to perform them.