Modern Fish Load Measures?

[dapellegrini]

So what is the rule now-a-days for fish load in an aquarium? Used to be 1-inch of fish per 1-inch of surface area, or 1-inch per 1 or 2-gallons, but these seem fairly out dated, for obvious reasons. (4-inches of clown loach or discus is not the same as say 4-inches of farlowella or dwarf puffers for example, and all aquariums are not equal...)

I would think that you would need to take into account your filtration flow rates, surface area, fish density (not just length), invert population, and plant density to start to approach a reasonably accurate measure... But then I may be over thinking the whole thing ... Anyone found a good calculator on the web? Or come up with a better way of deciding whether you should add that one more fish?

I currently use two methods (but am looking for something more scientific):

1) Busy factor - If the tank looks too busy, it probably is
2) IF you are wondering if another fish would be too much, then it probably would be.

 

[Jchillin]

Funny you would bring the subject up. Coolchinchilla submitted a very nice Article on this awhile back and it is appropriate now.

http://www.aquariumadvice.com/article_view.php?faq=2&fldAuto=47

 

[dapellegrini]

Thanks for the link JC... Definitely some good food for thought for folks that are new(er) to the hobby... I would recommend adding some mention of plant mass in a tank, as I don't think I saw that in the list of considerations... Another one that I just thought of is zones - balancing out your bottom, mid and surface water fish.

As for these newbie rules, it seems like we put these out there and use them initally, but then over time we establish a "gut feel" for things, and don't second-guess ourselves much until we see a big problem (see my 2 rules in OP). Just don't see many people coming back to some of the basic questions with a more complete understanding of the intricacies... to take it to a higher level.

To my original pondering, I am wondering if anyone has come up with a better way of coming to a measurable conclusion of an aquarium's current bioload and potential capacity, accounting for the various intricacies...

Perhaps the answer I am looking for is not worth the time spent finding it? Wouldn't be the first time... LOL --

 

[Mosaic]

Perhaps the answer I am looking for is not worth the time spent finding it? Wouldn't be the first time... LOL --

If you're advanced enough to consider plant mass, tank shape, and invert population, you can probably make a reasonable stocking judgment without needing a rule for it.
For the new people, the inch per gallon or inch per 12" surface area rule is great for limiting tank load, since they're probably tempted to overstock. It's sufficient, and I don't see much need to revise or update it. Usually when it gets mentioned here, I see we throw in a caveat that you need to allow extra capacity for goldfish or plecos or whatever.

 

[dapellegrini]

If you're advanced enough to consider plant mass, tank shape, and invert population, you can probably make a reasonable stocking judgment without needing a rule for it.

Ya, for any practical purpose, I think I would agree... If only my pursuit was practical....

Still, with just the bare minimum that (I think) we all agree on, we could supplement the rule with some slightly more complex calculations. Break fish into 3 levels, thick / medium / thin and apply a 1x / 2x /3x multiplier to the 1-inch rules. +10% for more than 3 turns of your tank water through filtration per hour, +10% for medium plant load, +20% for heavy plant load, +10% for 50% weekly PWC (EI dosing), etc, etc... I can't believe no one has done this before. We have these kinds of rules with the WPG, with different kinds of lights getting different multipliers assigned... You could make a little online calculator out of this and it wouldn't be that hard to use, AND it would force people to realize what factors they need to consider (by asking them to enter them)...

Hmmmm

 

[flyjawn]

i think it's a great idea... i agree that the one inch per gallon rule is good to start with but once you start learning more about your tank and your fish it sort of becomes obsolete because the variables are so wide tank to tank.

i think most importantly it depends on someone's willingness and ability to research and learn as much as possible about the tank they're keeping and the fish they want to keep in it.

 

[bosk1]

Hey, didn't Christmasfish start a thread on this subject over in The Lounge?

 

[dapellegrini]

Did a search and came up dry... bosk1, do you have a link?

 

[JRagg]

Did a search and came up dry... bosk1, do you have a link?

It's a thread called "christmasfish's answer to everything" or something of that sort. The at the end of bosk's post is a sign that nothing in that thread should be taken seriously. Seriously.

 

[kansei]

I guess as long as the fish seem happy - hiders can hide swimmers can swim and your filtration is up to the task you should be good , just remember that the fish will grow so it may look empty at first .

 

[Jchillin]

Did a search and came up dry... bosk1, do you have a link?

It's a thread called "christmasfish's answer to everything" or something of that sort. The at the end of bosk's post is a sign that nothing in that thread should be taken seriously. Seriously.

Here is the link, but like JRagg and Bosk1 eluded to, please don't take it seriously.

http://www.aquariumadvice.com/viewtopic.php?t=24716&start=0

 

[dapellegrini]

LOL, thanks.

I was thinking of a much more refined version of something like this:

http://www.publiclogic.com/fish/Fish_Count.xls

http://www.publiclogic.com/fish/Fish_Count.htm (if you don't have Excel)

How do you figure inverts effect bioload? Same as fish?

 

[Burks]

It all depends on the type of fish you are adding. Like you mentioned, adding a 3" Common Pleco is way different than let's say a 3" Danio.

Personally I used the "if I need to ask if this fish will be too much, don't buy it" guide. Currently I have a 14g most people would consider overstocked. But the fish are healthy, happy, and the water is fantastic. It's all in the proper equipment and fish selection.

 

[coldmachineUK]

I guess as long as the fish seem happy - hiders can hide swimmers can swim and your filtration is up to the task you should be good , just remember that the fish will grow so it may look empty at first .

Actually some of the most sage advice. I agree. "Rules" of 1-inch of this, that or the other, are actually extremely unhelpful even if they were reinforced by notions of type-of-fish, smaller vs. larger waste producers, and so on.

Really, if your fish are able to hide and can move a good distance around the aquarium, and you are filtering your water properly so params are within acceptable limits (0 amm, 0 nitrIte, 20 odd nitrAte), and youre keeping the tank clean (no piles of decaying poop on the substrate etc.), then there shouldnt be a problem.
IMO, 'rules' only encourage people to push their stocking levels 'to the limit', and it justifies people making poor stocking decisions.

$0.02

 

[Mosaic]

I guess as long as the fish seem happy - hiders can hide swimmers can swim and your filtration is up to the task you should be good , just remember that the fish will grow so it may look empty at first .

This is a very important point that I've been thinking about lately. Almost without exception, every fish in a store is a juvenile and will grow. Sometimes it's easy to forget, especially when dealing with the smaller species, so we need to keep it in mind.

 

[dapellegrini]

ColdMachine -- I agree, and this is really how I make my stocking choices. After 18 years in the hobby I have established a good gut feel for these things (or so I think)...

I still think it would be useful to have a better rule/calculator.

You will notice that in this quick sheet I put together, I measure fish load by adult length: http://www.publiclogic.com/fish/Fish_Count.htm

You will also notice that if you were to count my stocking levels with the normal 1-inch rule, I would be significantly overstocked, but I am not. I am not even counting inverts in this tally, which would potentially push me WAY over... but again, I believe I still have a healthy margin in my tank's capacity... I am making up the percentages based on plant load, etc, but my current thinking is that it would work something like this...

Anyone on the invert question? I don't remember anyone ever discussing inverts as part of a bioload, but they maybe should be? I have ~50 shrimp and ~50 nerite snails in there as well...

 

[dapellegrini]

Well, it was worth a try...

 

[coldmachineUK]

Oops, I forgot to reply to this one, it wasn't that I personally was ignoring the issue!
I like the calculator you've made: taking a look I can see the logic behind certain of the adjustment/compensation levels.
At the same time, you make a good point that in some cases fishkeepers can overstock tanks successfully with rigorous cleaning and water change routines in tandem with consideration for stock combinations: the gut feeling you describe is pretty much what I go on too, but I would never recommend to first time fishkeepers the sorts of stock levels I've seen others keep successfully. A calculator, or set of hard and fast rules, might risk the chance of someone deciding to 'push the rules to the limit'. Aside from thinking about the fish and trying to encourage people to keep them in the best sorts of conditions, the other reason I'm always conservative in recommendations to other people is that for some people losing the fish they're keeping or having things 'go wrong' means the end of their involvement in the hobby. The whole "well, I kept fish once but they all died so I didn't bother again" line which I've heard so many times before. That's a real shame when people's experiences are bad, purely because they didn't really understand what they were doing.

So, I think the calculator has merits for sure - it's certainly better than the one-inch-of-fish-per-gallon theory - but I still wouldn't recommend using any set of rules when it comes to stock levels since it really boils down to common sense.

 

[hc8719]

the one inch per gallon rule only works to a certain extent, you obviously cant put a fish that max out at 6" in a 10 gallon tank.

i'd say the inch per gallon rule only applies to lower activity fish that remain under 2"

 

[amosf]

As I said on andother forum. the inch gallon rule is over, gone, forget it.

It's time to go metric. it's 1cm per litre now