Stocking Levels

I've noticed that some people here seem to regard the stocking guide on Thinkfish as over generous and suggest that stocking levels should be below this. However, this is obviously in disagreement with the article on stocking levels which says “our guides are actually very cautious”. I wonder why there is this disagreement?

Personally, I tend to agree with the Thinkfish article. After all, we used to keep fish years ago based more or less on the 1 cm/litre guide with very poor or no filtration. Contrary to what one might expect, they didn't die or suffer from any apparent ill effects. With the addition of even the “standard” level of modern filtration more than 1 cm/litre should be easily supported. The Thinkfish article is obviously correct in also noting that there are several factors to be taken into consideration.

Although I have numerous aquarium books, from the 1950s to the present, most of which repeat the same “old” formula, I have yet to find any explanation of its origin. Has anybody ever actually conducted any experimental work on this? Or is it just another example of “received wisdom” passed down the years, the origins of which are lost? Was it just guesswork from the beginning?

It's a bit of a hangover from the old forum.
Bit of back history - Thinkfish was on a different host until spring 2012. There were problems with the host (the site had been running very slowly for some months, and sometimes it wouldn't even load at all) and the owner of Thinkfish was given a week to find a new host as they blamed the size of the database and Community Creator for the problem. He managed to save everything but the forum and CC. Six months later when the forum reappeared, the owner had rebuilt the CC with a few changes.
One of these changes was that he reduced the maximum stocking that a given tank was 'allowed' in response to criticism from other forums that stick rigidly to the "1 inch per US gallon" rule; that equates to 0.67cm fish per litre, a third less fish than 1cm per litre. The CC was very overgenerous in its first incarnation, and some of us oldies tend to forget that the current CC is not as generous as the old one 

I personally am also guilty of telling newcomers to the hobby to stock less than the CC says they can have to stop them going overboard for the first few months. Once they've got some experience, yes they can go up to the CC limit, and possibly beyond, as they will then have got to grips with tank maintenance and be familiar enough with their fish to know when something is wrong.

After posting my post above, I noticed that the levels in the filter compartments were all wrong and so I pulled out the large piece of black sponge that's first in line and squeezed that in some of the old tank water that I'd (fortuitously) been too lazy to throw on the plants. The filter's working fine now. I can't remember when I last squeezed the sponge out (a good 6 months, I'm sure - so before I got my tetras) so I wonder if it's slowly been blocking up and reducing the filtration efficiency over the past few months?

In the compartment following the sponge is this: Bio-home mini-ultra. If the flow is reduced then it's Nitrate removing capability is compromised.

Note to self: Squeeze filter sponge once a month.

Quote from: ColinB on March 11, 2014, 03:08:23 PM

Note to self: Squeeze filter sponge once a month.

Hi Colin, remember if you cut the sponge in half its easier to remove 

Hi Daniel - I remembered that I as was balancing on top of the steps trying to get it out without causing too much mess. 

I might try that next time. As it was, I just wanted the clean sponge back in and the filter up and running as it had been off for a couple of hours already.