Amount of fish per tank?

[statto]

Hello All,
I have read somewhere (on here I think) that a good ratio of fish to tank volume is 0.5" of fish length (not including tail) per 1Gal of volume.
Just a few questions
1) Is the above calculation correct?
2) Is the above calc reffering to overall size of tank or amount of water added?
(eg a 60Gal tank can take 30" of fish, does this reduce if 15Gal of that 60Gal is taken up with substrate and rocks, therefore leaving only 45Gal of water in which you could comfortably house only 22.5" of fish?)
3) For the purpose of this calculation does 'inches of fish' mean just fish OR every living thing in the tank (eg clean-up crew)?
Cheers
Statto

 

[marvin willis]

Originally Posted by Statto
http:///forum/post/2730257
Hello All,
I have read somewhere (on here I think) that a good ratio of fish to tank volume is 0.5" of fish length (not including tail) per 1Gal of volume.
Just a few questions
1) Is the above calculation correct?
2) Is the above calc reffering to overall size of tank or amount of water added?
(eg a 60Gal tank can take 30" of fish, does this reduce if 15Gal of that 60Gal is taken up with substrate and rocks, therefore leaving only 45Gal of water in which you could comfortably house only 22.5" of fish?)
3) For the purpose of this calculation does 'inches of fish' mean just fish OR every living thing in the tank (eg clean-up crew)?
Cheers
Statto
No its different for SW, say if you have a 55 gallon.
You can only have about 4-5 fish due to the bioload and territory

 

[bizzmoneyb]

It differs with the size of the tank and size/species of fish, but generally I think 1 fish per 10 gallons is a decent ratio for saltwater IMO.

 

[1knight164]

To be conservative, IMO, one inch per five gallons measuring from the nose to the base of the tail. Use the ADULT size of the fish, not juvenile. Subtract amount of water for sand and rock, add for sump/refugium. A good indicator in a well established tank will be the nitrate levels. Too high, too many fish. It's not a complete answer for high trates because there could be other causes but it's a start. Many of your more experienced hobbyists can overcome these problems and keep more fish, but I would start with this.

 

[dmyers557]

I've heard its 1 inch per 1 gallon in you tank. Of course you should measure the inch by adult stage length. Example is 34 gollon tank = 34 inches in full grown fish.

 

[socal57che]

Some fish are known for being messy eaters and some for their perpetual pooping. These factors must be taken into consideration when selecting fish. A 4 inch puffer or trigger has a larger impact than a 4 inch clown.

 

[niskyvaulter]

Originally Posted by socal57che
http:///forum/post/2730806
Some fish are known for being messy eaters and some for their perpetual pooping. These factors must be taken into consideration when selecting fish. A 4 inch puffer or trigger has a larger impact than a 4 inch clown.
ive never really seen this to be logical, at least when compared to herbivores. while a trigger may be messier than say, a tang, the tang has to eat a lot more food to recieve the same amount of nutrition b/c there is a lot less absorbable nutrition in plants and therefore will excrete more wastes. so shouldnt these two factors balance out the total waste produced by each kind of fish?
figuring out total amount of fish per tank is a very tricky thing. inches doesnt take into account effectiveness of filtration or behavior of the inhabitants. some territory fish may lower the fish count regardless of how heavily stocked the tank is. also, fish length is not totally a good representation of size. some fish are skinnier and some have more girth. compare a 24 inch eel to a 24 inch grouper, or a 3 inch neon goby to a 3 inch frogfish.

 

[socal57che]

Originally Posted by niskyvaulter
http:///forum/post/2731151
ive never really seen this to be logical
If you've ever seen a puffer eat you know they don't take in all the food. Much of it is wasted due to the way the puffer eats...messily. This food floats around the tank adding to dissolved solids (think algae bloom) and increasing the chance for high nitrates due to build up. This adds more to the biological load on the system than a fish that consumes all that it is fed. You count the poop from the fish then add what the fish wasted.

 

[mkzimms]

so in my 40G breeder with 20L sump would i be ok with 1 false perc, 1 potters angel, 1 sixline, and 2 bangaii?
i already have the clown and potters but im looking to pick up another few fish soon but have been really mulling over what to get.

 

[sickboy]

I don't see that combo being a problem, especially since you have the extra water volume in the sump.