Sorry for switching to Channel Jade, it will take ages if I try to reply in Chinese
Beautiful article from
littlepillow indeed, I think this is a very good extension of the very important thread started by
Macbrush, your explanation on the implication of filter technologies to the population limit of aquarium is very well written that I don't think I can better then that.
Regarding the bottom line issue, my position was basically clarified in the previous thread (quoted in my first reply to
littlepillow, I believed there is a need to setup a reference or suggestion or guideline (whatever that appropriate term should be, you know what I mean ) but I disagree with 1L - 1cm rule. Not that I want to propose 1L - 1cm, or 1L -2m, but I think figures like this is too simplified to be meaningful to hobbyist, as you have mentioned, consider the variety we have gained in the past 20 years, along side with the technologies and new products emerging at a very fast pace, I think the reference point have been shifted from space-based to quality based: quality of water, habitation, and aquarium management.
First of all, please pardon me for rolling back a bit and let me restate my opinion to the space-based reference. In another discussion, I said:
引言回覆:
1cm-2L水, bottleneck 是空間?是水質?還是其他原因?這 standard 從何而來?又是如何 generalise 到不同設定和管理的缸?
個缸可以養幾多魚,個人估計是非常 complicated, 和空間,水質,魚種,餵食,日常管理維護方法等都有關,很難想像可以 generalise 到1cm-2L水定1吋-1L水!
20L 水養 10cm 金魚用501濾桶,就不見得比 20L 養 20cm 燈魚用501濾桶更健康!
引言回覆:
其 實大家的 feedback 大致相同,就是缸的變數實在太多,單一數字,又欠任何 qualifying factor,於是這數字便出現實際使用上的困難和欠說服力。無論是 reference 又好,guideline 又好,baseline 又好,單一數字就有較大機會出現問題。
要處理6cm 的七彩神仙,同處理三條 2cm 燈魚的分別實在有太大分别,除體積分别外,前者本身分汾多,又對水質敏感,後者則需較多工夫去營做 habitat。湖鯛在人工養時需藉超養來模糊它們的地盤觀念。金魚和錦鯉不要求水深,但要有長位比佢游,和要加倍的物理過濾,.....等等。因此我很 難理解單一數字可作為 meaningful reference/guideline/baseline。
我真心相信有討論和 discourage 超養的必要,但我又真係接受唔到無任何 qualifying factor的單一數字作依歸。我們日常的接觴到與生態環境有關的guideline, 如空氣污染指數,UV 指數等都不會是單一數字,所以我覺得採用一個 range是較易接受的,亦較有指引性。
This explained why I disagree with 1L - 1cm or whatever similar reference. Maybe as you said, we can use this as a reference for the general public, but I don't think this is a meaningful reference for hobbyist at all, not even when we relax it and set it to 1L - 10cm.
The least we can do, is to implement two changes into this reference. First of all, I suggest we change the measurement of fishes from length-based, to volume-based. We have to figure out an acceptable and meaningful way, such as 10L - 1 cm3, or 10L - 5 tetra. Secondly, I think as a reference, we should set a range rather than one specific figure, such as 10L - 5 to 10 tetra depends on the quality of water, habitation and routine management. Be reminded that I am proposing two directions of changes at this point, not that I propose any new figures or new reference.
On the other hand, if we want to set a reference for hobbyist, I suggest we pick something that is related to the "potential" problem and provided direction to the players. I have mentioned three quality issues above, this is not mean to be exhaustive but for discussion purpose, let's stick with vital characteristics of water, habitation (including space issues) and routine management. I'll share my thoughts but again, these are preliminary thoughts from someone who just started this hobby not too long ago, so please correct or compliment whenever you consider necessary. On the other hand, as reference, we should try to stay simple and yet meaningful, this is a difficult balance to strive for.
Vital characteristics: I would say temp, pH and the nitrogen cycle (NH3/NO2/NO3) are the vital characteristics for healthy fishes, and the N cycle is the one that can be directly related to fish population. I suggest we use NH3 = 0 as the reference, so if you notice the NH3 level of your tank raised to a higher level, that means the N cycle is unable to convert the waste to NO2 and possibly caused by over-crowded. If you want to develop a more comprehensive guideline along this line, I think this post will give you some useful figure to start with:
http://www2.aqugrass.com/phpBB2/viewtopic.php?t=46521
Habitation: we can adopt something like 10L - 5 tetra as a quick reference on the space issue, but if we have the resource, maybe we can develop an addition reference that reflect the specific inhabitation of the fishes we have. For example, we can consider having enough space for the fish to swim in straight line for 10 body-lengths is acceptable, 20 body-lengths as good, and only 5 body-lengths as not acceptable. Be reminded that when I said 10 body-lengths, I don't mean the horizontal dimension of the aquarium. What I mean is, we should observe the movement of the fishes in our aquarium. If we saw the fishes always run into another fishes within 5 body-length and need to steer away to avoid bumping into each other, this is bad. Again, I am not proposing 10 body-lengths or 5 body-lengths here, I just want to suggest a direction that we should explore.
Finally, when we come to routine management of aquarium, there is no quick reference, I think the better way to tackle this s is to compile something like 10 Do's and 10 Don'ts on Aquarium.
Anyway, this is just the start of a very constructive decision; keep it up, my friends.
![:-n05](./images/smilies/icon-05.gif)