HeHe蝦蝦 寫:
多謝各位解答.
我上網睇資料, 容量, 裝濾材量, 電量其實相差唔係太多,
但價錢就好多, 所以想知道會唔會效能上有好大差別.
Ehiem 係大廠, "我想" 佢唔會出d產品會差, 但濾桶的功能都係大同小異, 唔同品牌唔同價錢可以理解, 但點解同廠, 在差唔多的 spec. 下......
所以會想到 221X series 會唔會係差 d (no free lunch in the Earth). 圓桶和方桶的 design 上會令效能相差很大嗎? 入水口的位置, 和出水口的大細會影響效能嗎? 點解 Ehiem 會咁樣 design 221x series , classic 點解? 而 professional 對比 classic 又有幾 Peofessioanl 呢?
好想搞楚先至買. 唔 mind 比多 d 錢買個好的, 但就係想知原因.

Sorry, it is kind of long and serious, so have to resort to English as it is quite late.
221x series use "old" technologies, which is proven to work in many cases. The round shape created smoothest water circulation inside the filter, the inflow water is directed to the bottom of the filter and let the dirty water work its way up through gravity feed, this is the most efficient arrangement as it does maxima the height different and in turn increased the gravity feed pressure. For mechanical filtering, I can't think of better arrangement.
However, the 221x design does exhibit some shortcoming in daily use. While you can stuff a lot of filter substract into it, they are all stacked up one over the other, which mean when you need to clean the substrate at the bottom, you have to take out all the substrate one after the other. When other competitor introduced drawer approach to organise the filter substrate, users welcome that idea and Eheim has to follow suit, so they revised their filter to incorporate several "drawers" to hold substrate in "compartments". This approach does make it easier to clean and maintain the filter, but will significantly reduced the amount of substrate that can be placed inside the filter, as a result of that, they have to increase the volume of the filter in order to maintain similar substrate capacity, so they changed the round design filter chassis into the current round-corner rectangular chassis.
The inflow of new 202x series are placed at top of filter, this is easier to control for most users, and eliminated the need of two set of "double water tape" (雙水閘). The dirty water, while enter the filter from the top, will be directed to the bottom of the filter and then work it way up, it does share similarity reasonale of the Classic series, but is less efficient relatively.
As I said, 202x has more powerful filter head and is more convenient to use, 2215/2217 is very efficient and proved to work, but slightly inconvenient to use.
Hope this helped.
