richie10093
Aquarium Advice Newbie
I can not begin to say how many times this question comes up, but every time it does, this is a fairly serious question that needs to be addressed. so to try and address it, I've 'made up' a system that I've been using since no matter how hard I look, I can't seem to find a solid answer. I wanted to run it by you guys here, and if anybody from saltwater wants to chime in that would be fine too, but for now I am more specifically targeting freshwater.
this is not going to cover the number of fish you can keep. merely the 'max size'
I started off with a "max sized fish for your tank rule" I found somewhere awhile ago that said the tank should be at least 4 times as long as the max size of the fish and 2 times as wide as the max size of the fish. this is good because it accommodates the fish and allows it to be able to move fairly freely even with most typical decorations in the tank. however this is not suitable for more active fish. yet, for most "lazy" catfish and plecos that spend the majority of their time stationary, this may not be the worst guide. so for moderately active fish that would passively search around the tank, such as many south American cichlids, I would divide the smallest of the previous numbers by 2, and to keep highly active fish such as rainbow fish, divide by 2 a second time.
to help clairify this with actual numbers , let's look at a standard 55 gallon tank. this is a fairly common size for people to begin wanting larger fish. they are typically 48" long and 12" wide. now 48/4 = 12" and 12/2 = 6". so idealy the largest size for "lazy fish" would be around 6". and this divided by 2 would mean the largest moderately active fish that should be in there should be around the 3" mark. and for rainbows or other highly active fish this would mean 1.5" is about the largest they should be in a 55.*
I will now do the math for a few other standard tanks and put that below so that you can look at the numbers and see how you all feel about them, however, what I really want is feedback on how this could be modified to help provide more ideal yet realistic conditions to all fish.
approximate maxes for activity levels
*tank size *Lazy *Moderate *active
10 G -5 -2.5 -1.25
20 High -6 -3 -1.5
20 Long -6.5 -3.25 -1.625
29 G -6 -3 -1.5
30 G -6.5 -3.25 -1.625
40 breeder -9 -4.5 -2.25
55 G -6 -3 -1.5
75 G -9 -4.5 -2.25
125 (6ft) -9 -4.5 -2.25
180 (6ft) -12 -6 -3
(sorry about the long post and the formatting of the numbers. I didn't know how to do it any better
this is not going to cover the number of fish you can keep. merely the 'max size'
I started off with a "max sized fish for your tank rule" I found somewhere awhile ago that said the tank should be at least 4 times as long as the max size of the fish and 2 times as wide as the max size of the fish. this is good because it accommodates the fish and allows it to be able to move fairly freely even with most typical decorations in the tank. however this is not suitable for more active fish. yet, for most "lazy" catfish and plecos that spend the majority of their time stationary, this may not be the worst guide. so for moderately active fish that would passively search around the tank, such as many south American cichlids, I would divide the smallest of the previous numbers by 2, and to keep highly active fish such as rainbow fish, divide by 2 a second time.
to help clairify this with actual numbers , let's look at a standard 55 gallon tank. this is a fairly common size for people to begin wanting larger fish. they are typically 48" long and 12" wide. now 48/4 = 12" and 12/2 = 6". so idealy the largest size for "lazy fish" would be around 6". and this divided by 2 would mean the largest moderately active fish that should be in there should be around the 3" mark. and for rainbows or other highly active fish this would mean 1.5" is about the largest they should be in a 55.*
I will now do the math for a few other standard tanks and put that below so that you can look at the numbers and see how you all feel about them, however, what I really want is feedback on how this could be modified to help provide more ideal yet realistic conditions to all fish.
approximate maxes for activity levels
*tank size *Lazy *Moderate *active
10 G -5 -2.5 -1.25
20 High -6 -3 -1.5
20 Long -6.5 -3.25 -1.625
29 G -6 -3 -1.5
30 G -6.5 -3.25 -1.625
40 breeder -9 -4.5 -2.25
55 G -6 -3 -1.5
75 G -9 -4.5 -2.25
125 (6ft) -9 -4.5 -2.25
180 (6ft) -12 -6 -3
(sorry about the long post and the formatting of the numbers. I didn't know how to do it any better