Fish Bioload Thread

[SoloChromis]

It's been said that 20 clownfish equate to 1 average sized tang, or that a blenny for example, carries a bigger load than a goby of similar size (due to the blenny's herbivorous diet). I think a definitive reference sheet would be helpful to those considering their potential livestock list for a tank. Obviously none of this is expected to be *completely* and totally accurate, but just an idea of the biological weight of a certain group of fishes would be helpful I think. So have at it guys...

* Clownfish
* Anthias
* Large Angels
* Dwarf Angels
* Eels
* Damsels
* Gobies
* Tangs
* Blennies
* Puffers
* Lionfish

... etc. Thanks everyone

[CoralNerd]

Great idea following along.

[Genera]

Originally Posted by coralnerd

great idea following along.

+1
The waste of one 7" goldfish is equal to the waste of 15,000 guppies. (I love hyperboles)

[CoralNerd]

Originally Posted by Genera

+1
The waste of one 7" goldfish is equal to the waste of 15,000 guppies. (I love hyperboles)

I guess I bought it hook, line, and sinker, but there is truth to what he's saying. It's somewhat obvious but sometimes you get a fish and your like wow this guy is a real pooper. Right now I'm trying to get my nitrates up so I have been feeding my fish like crazy to get my corals happy.

[Genera]

Originally Posted by CoralNerd

I guess I bought it hook, line, and sinker, but there is truth to what he's saying. It's somewhat obvious but sometimes you get a fish and your like wow this guy is a real pooper. Right now I'm trying to get my nitrates up so I have been feeding my fish like crazy to get my corals happy.

I have some goldfish in QT along with 5 guppies in a different QT. I have to do daily 50-75% water changes to keep ammonia levels at bay. The guppies I do a 25% every week and the ammonia levels aren't really that high in the first place.

[CoralNerd]

Originally Posted by Genera

I have some goldfish in QT along with 5 guppies in a different QT. I have to do daily 50-75% water changes to keep ammonia levels at bay. The guppies I do a 25% every week and the ammonia levels aren't really that high in the first place.

Ok we get it. I think this thread has been hijacked

[Genera]

Sharks and rays produce massive amounts of waste called urea which is even more ammonia packed than bony fish waste. Say a small 1 foot bamboo shark produces as much waste as maybe more or less than 50 2-3in damselfish.

[DubiousMaximus]

maybe there should be some sort of scale created?
Scale: 1 - 10, one being very little to no detectable wastes such as a snail and ten being larger animals like a shark or ray. Could even maybe test the nutrient levels of a single fish over 4 days to find the production value

[Dkuhlmann]

Ok going along with this, my 1" Cherub Angel craps about 3x more than my two True Perculas (m- 1 1/2" f-2") LOL but true.

[SoloChromis]

Originally Posted by Dkuhlmann

Ok going along with this, my 1" Cherub Angel craps about 3x more than my two True Perculas (m- 1 1/2" f-2") LOL but true.

Good info. So it's been established that herbivores (like your angel) create more waste in a tank than carnivorous fish that are similar in size and body shape

[SoloChromis]

Originally Posted by DubiousMaximus

maybe there should be some sort of scale created?
Scale: 1 - 10, one being very little to no detectable wastes such as a snail and ten being larger animals like a shark or ray. Could even maybe test the nutrient levels of a single fish over 4 days to find the production value

This would be ideal, so those of you quarantining would have especially helpful experience with this. The scale should definitely apply as well, 1 being your average invert, and 10 being a decent sized shark or ray

[SoloChromis]

Originally Posted by CoralNerd

Ok we get it. I think this thread has been hijacked

Not necessarily, I think that's pretty valuable information, even if it's freshwater

[SoloChromis]

Keep in mind a fish's metabolism, such as anthias for example. They must be fed more frequently than many other fish, therefore their biological footprint on a tank will be much larger, despite their diminutive size

[Dkuhlmann]

Originally Posted by SoloChromis

Good info. So it's been established that herbivores (like your angel) create more waste in a tank than carnivorous fish that are similar in size and body shape

I meant 3x what the pair together produce

The Cherub Angel eats constantly off of the rocks and glass and the sand. The Perculas only eat when I feed them.

[woodnaquanut]

Originally Posted by SoloChromis

Good info. So it's been established that herbivores (like your angel) create more waste in a tank than carnivorous fish that are similar in size and body shape

I'm not sure you could make that a rule. If you consider waste by volume or weight that might be true. The nutritional value of the waste is most likely much higher for carnivorous fish. I'm just guessing here but they do eat much more nutritionally dense food.

[SoloChromis]

Originally Posted by Dkuhlmann

I meant 3x what the pair together produce

The Cherub Angel eats constantly off of the rocks and glass and the sand. The Perculas only eat when I feed them.

A good point to keep in mind when considering the potential bioload of fish. Fish that are constantly nipping and grazing on things are bound to produce more waste, as opposed to fish such as clowns, chromis, cardinals etc. All of whom only really eat when you feed the tank.

[Dkuhlmann]

Originally Posted by SoloChromis

A good point to keep in mind when considering the potential bioload of fish. Fish that are constantly nipping and grazing on things are bound to produce more waste, as opposed to fish such as clowns, chromis, cardinals etc. All of whom only really eat when you feed the tank.

Exactly, and that's why I've over killed it with my tanks ability to process that high bioload. I'm running for my 30 gal DT, 20 tall sump about 65 or 70 lbs of lr and would total 4-5 inches of sand split between the two. 3" in my dt and 2 in the sump. I've also got a large ball of chaeto and a 70 gal protein skimmer. Currently only 4 fish. Two perculas, one Cherub angel and one Hector's goby. I'm upgrading to a 40 b and will be adding 3 more fish. McCoskers wrasse male, royal gramma and probably a yellow watchman goby Not sure on adding pistol shrimp yet. BUt that's all I want in my tank for fish. I've got mixed corals SPS, LPS softies and two BTA's. The current 30 gal can handle probably twice the current load that I've got because of my export abilities.

Oh and I feed very heavily. I like fat healthy fish

[PIPSTER]

Poop is different than "pee", which salt water fish are doing 100% of the time. It would be nice to know which fish have higher "ammonia output". Fish poop seems less important for toxins, and more important for coral food....???

[Shawn O]

It certainly would be nice to have some sort of scale or point system to go by, with each fish having a certain number of points. Pick your tank size and equipment, get a good rough number for bio-load to stay under and presto! Someone here needs to make a calculator app.

Before I got into fish I just kind of figured using mass as a guide would be good enough. It only makes sense that a 4" clarkii should be equal to 5 or 6 zebra dartfish, doesn't it? If only it were that easy....

[LobsterOfJustice]

In my opinion, it doesn't matter what fish are in the tank, it's how much (and what kind) of food goes in the tank. If you feed a cube of mysis a day and have no fish, or 10 damsels, or one tang, the tank has the same amount of nutrient input. If you've already got 10 fish and you buy one more, but you don't feed the tank any more because of it, you haven't increased bioload IMO.

That said, I would also point out that higher protein foods result in more nitrogenous waste (ammonia/nitrite/nitrate). So if you trade out some of the mysis for nori in the diet of your herbivores, you might see a little less nitrate build up. I'm not sure how significant this is, but I always let my large herbivores fill up on a sheet of nori before feeding the rest of the tank mysis/shrimp.

[Sk8r]

Damsel and clowns are about identical, depending on size of species, granted they're roughly the same fish, same behaviors.

Blennies and gobies are about the same as each other, except that one will process film algae and the other will process sand gunk---weight for weight, they're both an asset if they leave what you value alone. They tend to process waste pretty well. Toss jawfish into that pile. Some gobies like the dragon really move sand, but others like the yellow watchman, same size and general look, are much more sedate. In all, they're more processors than outputters if they're backed by a good complement of bristleworms.

[mattsilvester]

As a note aside, in my experience you will reach the territorial capacity long before you reach the biological.

Also, nothing is worse that uneaten food and other decaying matter - so some fish as Sk8r points out will probably be a net consumer rather than net contributor of the "bio-load" - or at the very least "cost neutral".

In terms of stocking rates; I think that the 1" per 5 gal rule is a good guide, but no one will argue that a 6" tang or angel cannot be compared with 3 x chromis or clownfish; both in terms of bioload capacity and overall territorial or "living space" capacity.

To that end, I stick with some rules of thumb such as:
- typically, "medium" and "large" fish such as tangs and angels will reach about 60% their size in the home aquarium and then spend years trying to do the remaining 40%. So a fish that will get 8-12" maximum size will probably get to about 6-8" in the some aquarium, max size 6-8 probably about 4-6" etc.

- the 5 gal rule applies to medium sized fish i.e. those that will "probably" reach about 4-6".

- for bigger or smaller fish, the 5 gal rule should probably be adjusted up or down by about 50% for "living space"i.e. small fish like chromis can probably be allocated 1" per 2-3 gallons while bigger fish like angels and large tangs probably about 1" per 7-8 gallons.

- for bio-load, I think similarly those that fall into the small catagory are probably about 50%, but those that are big should be doubled (+100%).

As with anything, all the above should be taken with a grain of salt and there are so many additional factors such as:
- what is fed, in what quantity, when and how often (small feedings multiple times per day, or once a day gorging).
- what is the shape of the tank (arguably, deep tanks provide lots of volume but less space).
- the mix of fish; a good mix whereby some fish will literally eat the poop of others, and not compete for territory will be more efficient in terms of stocking capacity.