General Question About Lfs Fish

SPiNoVA
  • #1
When I read descriptions of fish online, it will say things like 'Maximum Size: 2 inches'. Yet, a lot of the times, the fish don't actually grow much once they're in the tank. For instance, the WCMMs, guppies, platys, etc. that I got appear to have not grown much at all, while I can see that my Ram has definitely grown some in a short amount of time (seen that in goldfish, angels, etc.). And some of these smaller fish are nowhere near their alleged maximum size. For instance, I've read that cardinal tetras can get to be 2", yet in all the online videos I've watched, they're all about half that size.

So, is there a particular age at which LFS get their fish? I'm assuming that the smaller fish is about as big as they're going to get (generally speaking), while the larger ones will have more room for growth? Would the smaller fish achieve their potential max size if they were in larger tanks?
 
Advertisement
Demeter
  • #2
Snaller fish like tetras, barbs, platties, guppies, danios etc are usually sold as young adults. They will grow but not too much more. That being said, depending on the breeding stock and how well the fish were taken care of, some fish will never reach max size while other of the same species will exceed max size. Plus some fish grow much slower than others.

Larger species such as cichlids, goldfish, most catflish, loaches etc. are sold as juviniles so they will grow a lot more.
 
Platylover
  • #3
Just to add, a lot of times for a fish to reach their max size it takes several years. So if you only have the fish for a year or two it’ll more than likely not reach it. Most fish when they become adults also aren’t right at max size, but since they’re adults their growth tends to be very slow(unless they were stunted, then they can have a huge growth spurt) thus taking several years to become max size. As already stated, the care and breeding involved also as a huge impact on their personal max size.
 
Advertisement
fissh
  • #4
fish keep growing until the day they die, so the max size is determined by how long the fish lives, assuming that all other basic needs are met.
 
Mcasella
  • #5
I had sibling bn plecos that lived together for a while, both females, one reached a monstrous five inches at 1 year old, the other barely 3 inches at the same age - same care, same food, same amount of space. Just one displayed a better show of genetics than the related one.
This can be seen in fish over time some grow some do not even with the same care/etc.
my neons, half are 2 years old (as long as I have had those ones), I have four that are much older, and my biggest ones as well, they all have cataracts in one or both eyes and definitely prefer being in with a large school as opposed to stuck in a store tank after their owner brought them in, this same store sells juvie neons at 3/4-1 inch in size.
Ime cichlids, even dwarfs, and other south american fish seem to grow much faster - comparing growth of my apistos to my young angels is also a gaping difference, but the apisto start to sex out at 3-4 months old and angels are over twice that age when they start to show sexual maturity.
 
Advertisement
tyguy7760
  • #6
There are also fish that are known to get larger in the wild than in aquaria. Many times these sites will quote sizes in the wild but those sizes are rare in an aquarium. Oscars and Rainbow cichlids are two that come to my mind.
 
Mike1995
  • #7
There are also fish that are known to get larger in the wild than in aquaria. Many times these sites will quote sizes in the wild but those sizes are rare in an aquarium. Oscars and Rainbow cichlids are two that come to my mind.

if an Oscar is given a big tank, it will grow massive, sometimes more than 15". Mine are getting close. Most of the time Oscars don't grow or live long because people have them in small tanks.
 
tyguy7760
  • #8
if an Oscar is given a big tank, it will grow massive, sometimes more than 15". Mine are getting close. Most of the time Oscars don't grow or live long because people have them in small tanks.
agreed. but I know of some accounts where oscars have been collected in the wild over 18 inches. This being exceedingly rare in aquaria even with the proper tank size.
 
DuaneV
  • #9
Theyre growing. Always. It doesn't happen over night. When you have tetras, that CAN live up to 10 years, they don't get 2" in a year. AND, when you get a fish that's 1" long and its max size is 2", you won't notice it getting bigger. Just like a person, you don't notice a pound or two, but every year when my 9 year old goes to the doctor and weighs 10-15lbs more than last year, you know he's growing. I find a LOT of fish sizes posted at the LFS are actually off on the smaller size. They have plecos listed at 12-16". Ive never had one that wasn't 20" or bigger. Oscars are listed at 12"+. Every Oscar I ever had got to be 12" in a year. First Oscars I ever had were in a 55 gallon cause I didn't know any better, and they both got to be over 20".
 
tyguy7760
  • #10
As someone else mentioned in this thread, genetics plays a huge roll in the max size of any given fish as well. how many times a fish's predecessors were line bread, how distant a fish is from a wild caught, water quality, water temp, lots of things play a roll.
 
abcdefghi
  • #11
if an Oscar is given a big tank, it will grow massive, sometimes more than 15". Mine are getting close.

Have any pictures? I would love to have an Oscar one day, but likely never will due to preferring community tanks than giving a large tank up for a couple fish.
 
SPiNoVA
  • Thread Starter
  • #12
I hadn't realized that fish don't attain maximum size roughly at the same time they hit sexual maturity. Good to know!
 
fissh
  • #13
I hadn't realized that fish don't attain maximum size roughly at the same time they hit sexual maturity. Good to know!
Just like human teenagers!
 
tyguy7760
  • #14
chromedome52
  • #15
Most of the growth in a fish's life happens prior to sexual maturity. At that point it slows, especially for females as their energy goes into egg production rather than growth. Males will continue to grow a bit faster, but they still slow after maturity. Growth is greatly influenced by external factors, but there is also just the simple variable of genetics that will cause one fish to slower growth, while a sibling can turn into a monster. Not all fish of the same age are the same size in the wild, so it's silly to expect it in aquaria.

The small Tetras, barbs, and minnows are sold at only a few months of age. If one treats them well, they can grow quite large in a short time. Most of these fish reach sexual maturity at 9-10 months of age, and their growth slows. The problem is how long they sat at the fish store. Stores do not normally feed the high quality food they need for further growth, so they can be slowed or even slightly stunted if they sit in the store too long. Best to buy asap after they arrive at the store. I've seen recommendations to wait a few days to see if they are healthy, and that probably won't hurt, but I wouldn't buy fish that have been in the tank for a couple of weeks or more if there's a choice.

I have seen Cardinals that were over 2", but from talking to the owners, they all had the fish for 4-5 years and fed them very well. Live foods will always be better than any flake, pellet, or frozen food. In the wild they reach that size in less than a year, because by that time they are facing near certain death from the next dry period. But they also have an environment that provides a nearly constant supply of food.

So what it comes back to is the quality and amount of food, the water quality, and space. I've raised fish that never saw a flake or pellet, strictly live foods. It's not really that hard any more to keep food cultures going. Maintaining water quality means water changes. I think I've said it before: You can replace filtration with water changes, but you cannot replace water changes with filtration. They are vital, I've seen the evidence time and time again. And as for space, whatever you think is necessary, triple it if you want your fish to really grow. I've seen a 3" Zebra Danio, it was raised in a 240 gallon plywood tank. The owner had several species of fish that are normally thought to be small, and all were twice the size you usually see. Food. Water. Space.
 
SPiNoVA
  • Thread Starter
  • #16
First of all, what sort of live foods does one feed fish, and how does one keep a live food culture going?
 
abcdefghi
  • #17
First of all, what sort of live foods does one feed fish, and how does one keep a live food culture going?

Bucket of water left outside in the summer, free mosquito larvae live food all summer long.

That's the extent of my live food culturing, but I know there are cultures for various worms, bbs etc that you can set up. I just have no idea how, but would one day like to set something up when I have time and space.
 
DuaneV
  • #18
I feed mine live mosquito larvae, live brine shrimp and live daphnia. I grow it all myself in various ways. Some in 2 liter bottles (brine shrimp), some in outside buckets all summer (mosquito larvae) and some both (daphnia). If you have bigger fish, like Oscars, you can feed them live fish, crazyfish, frogs, etc. Been there, don't that too.
 

Similar Aquarium Threads

Replies
9
Views
599
dojafish
Replies
19
Views
589
Rooks
Replies
12
Views
718
wapooshe
Replies
56
Views
4K
aliray
Replies
29
Views
2K
Reyes
Advertisement

Advertisement


Top Bottom