Fry growth--large cichlids etc....

[CRaZeeeBiTcHisH]

Hello! I am new to this site, hope no one is offended by my name, but it usually fits....
I have at present 5 running tanks-biggest of which is my big babies--yes oscars! 8) ya gotta love em...Does anyone else here keep large cichlids? particularly south american or central? I have 9 juves (shooting for a pair) in a 90 gallon with some small convicts that shoot around the bottom...(they are very prolific as most of you know and they provide lots of live foods... )
Point of my rambling post is this--I have one tank which is divided into 3 equal sections, mainly for separating different stage fry, and in one partition I have probably 20-25 pink convict fry from one single spawn. They are the only pink convict fry in the tank, so all are the same age. Recently crunched for space, I needed to quarantine a new rather sensitive fellow, so I placed him in one of the partitions of the same tank. In trying to entice him to eat, I put 5 baby connies in his section. Of course he turned up his nose at my offering, but I left them in there with him anyway just in case he changed his mind. Well--after 1.5-2 weeks, these 5 connies were almost twice the size of the ones in the original partition. How does this happen in the same tank with the same water and same food? I have read that the less energy the fry expend to find food the faster they grow-which relatively it would seem these guys would work harder because they have more water and less available food given to them because of the lesser total number. I always feed them very carefully-slowly to try to make sure everyone gets some, and they get fed rather frequently. Water quality is excellent. pH is 7.4,ammonia, nitrites and nitrates are immeasurable, temp is 82 degrees...could this be the result of less competition for food? resulting in these fry receiving a greater quantity per fish? Does anyone have any idea besides warm water and frequent feedings to increase growth speed? They do get frequent water changes, so the water quality is consistent as well....could it possibly be the extra exercise? The original guys have plenty of room to maneuver around, but there are quite a few more in there (but they are by no means crowded at this tiny size ).
Thanks to all who reply in advance!

 

[reefrunner69]

I would think it's three things,

1. First and foremost is space, the other fry may not be crowded, but they are more so than the few in the other partition.

2. Even though the other fish is not their parent, the fry are most likely feeding on th slime coat of the adult fish, this is quite common in cichlids and is probably the main reason for the accelerated growth 8)

3. Availability of food, I know you said you are careful feeding them, but the simple fact is, less fish = more food. The larger fish in the partition is aalso feeding and cichlids are messy eaters, so the crumbs and bits that are floating around from it's feeding are fair game to the fry.

HTH

 

[CRaZeeeBiTcHisH]

Thanks for the help--would you think I would have faster growth in all the fry if i spread them a little thinner then? If they were feeding off his slime coat, they have since quit, because he has decided they taste pretty good! I think they are a little big for him to eat, but he sure does chase them when he sees them...

 

[reefrunner69]

Typically the only fish that allow this are the parents, since the fish in question has taken a dislike to the fry, I'd say no don't put more in with him. Even if they are too big for him to eat, he will terroize them, possibly leading to disease. All the fry will grow faster with more space, so if it is possible, give it to them.

 

[fishfreek]

Take this post for a grain of salt but I do belive I had read this someplace and it might be helpful.

When you say they are using the same water are your partions setup so the water is shaired amongst all the sections are are they totally seperate and the water is the same meaning that it is comming from the same source.

If the tank is acutally three seperate compartments where the one in the middle could be full with water and the two on the ends could be dry then I have this to add.

I read that fry release some from of growth hormone into the water. The person in the article was saying if you had two batches of fry and changed the water very reguarlly in one batch and did ont change the water in the second batch that the batch that did not get water changes would have their growth stunted and could very well never grow to full adult size.

They where explaning it as to have to do with this hormone being released by the fry.

Also, its known that fish will grow in proportion to the tank size they are held in. If you have two small fish of equil size and put them in different size tanks they will grow at different rates. But this was already touched upon by kevin.

 

[CRaZeeeBiTcHisH]

Tried to post once already, so if I did it twice, I apologize in advance
The partitions are covered in small holes to allow water to flow through, so I doubt hormones played a part, although I have read about that theory. I do have to pick a bone with a fish not outgrowing it's tank though 8O --hope I don't seem too controversial on my first day..lol...many fish will outgrow their tank if the water is kept clean. Nitrates do however do stunt grow quite effectively if allowed to rise too high(which would happen quickly with a large fish in a small amount of water, or with poor aquarium maintenance, that is, lack of water change or gravel cleaning)--One of my oscars, my favorite i might add..hehheee, was an orphan that outgrew her 5 gallon tank. The fish store is full of them in the back...different kinds of course, but lots! sad, i know... I have even read of people who practically starve their fish to slow it's growth as much as possible...

 

[reefrunner69]

Not too controversial..... , I agree with you that fish will, if capable out grow their tanks, but Aaron hit upon the fact that tank size will effect growth rate, not end size. A large cichlid will take longer to out grow a 20g, that to reach that size in a 125g. If you see what I'm saying.


on a side note...It's starting to get stormy here again, so this may be my last post for several hours

 

[CRaZeeeBiTcHisH]

Aaron hit upon the fact that tank size will effect growth rate, not end size.

I don't have any personal experience to agree or refute that one...but...naturally...i got another question...

Assuming that there is not a growth inhibiting factor released into said aquarium, and nitrates are kept reasonably low (or none), and all chemical factors are equal, do you have any theories as to why this would occur? Do you think it would be related to their swimming room and exercise, perhaps easier for them to find food since it may be spread over a wider area initially, or something else? I am quite interested in this as you can probably tell. I was shocked at how fast those little connies grew in that end of the tank, needless to say, I would love to reproduce it on a larger scale...I could spread them a lot thinner with some effort if it would make a large difference. And I am sure my oscars would thank me at this point if some actually grew big enough for them to see! LOL--they don't even notice these little boogers! Thanks again for the speedy response...I am gonna hit the sack myself--working nites...ewwww, hope you weather the storm well

 

[reefrunner69]

As I said in my first post, I believe the fry were munching on the slime coat of the larger fish. This is quite common if the fry are left with the parents (cichlids only). It is commonly known that fry left in the tank with the parents, will grow twice as fast as those moved to a seperate "fry tank".