Platy fry not growing

i have had 10 platy fry for almost 7 months now and the biggest fry is only about a half inch long. they are in a 10 gallon setup with a heater and sponge filter. Does anyone know why they aren’t growing?
my ph is neutral, ammonia is 0ppm
nitrite is 0ppm and nitrate is 5ppm

 

My wife has told me before they need adult hormones around to grow. I don't know if there is truth to that. I don't really do much with the platies but water changes.

 

What are you feeding them and how many times a day? How is your lighting in the tank?

 

Flakes mostly. I give them some pellets made with meat a couple times a week when she isn't looking.

 

What are you feeding them and how many times a day? How is your lighting in the tank?

i’m feeding flakes and bloodworms twice a day and the lighting is medium

 

i’m feeding flakes and bloodworms twice a day and the lighting is medium

How much were you feeding initially? Fry usually need tons of feedings anywhere from 5-10. They can eat every ~30 minutes or so. Platy fry usually fully grow within ~3 months, so that's kind of a red flag that yours haven't fully grown within 7 months. Also, some adults don't make it past an inch, the bigger ones are usually the ones being sold retail, so it could be just a smaller bach in general. How's the coloration on them? If they're fully colored and about an inch in size they could actually be fully grown.

 

How much were you feeding initially? Fry usually need tons of feedings anywhere from 5-10. They can eat every ~30 minutes or so. Platy fry usually fully grow within ~3 months, so that's kind of a red flag that yours haven't fully grown within 7 months. Also, some adults don't make it past an inch, the bigger ones are usually the ones being sold retail, so it could be just a smaller bach in general. How's the coloration on them? If they're fully colored and about an inch in size they could actually be fully grown.

for the first few days i fed them constantly and when i wasn’t around i dropped in pellets for them to nibble off. their colors are starting to come in but they are still mostly pinkish. they were a cross between a red wagtail and a yellow mickey mouse. i can also tell male vs female so at least they’re developed enough for that

 

The craziest thing just happened, I was looking at the fry tank and I see the tiniest baby fish ever. Half the size of most livebearer fry. My fish in the fry tank aren’t even 3/4 of an inch long, yet they had a baby??? How is this possible? Are the ones I have just runts? They don’t even have adult colors, only some patterns. I am extremely confused.

?

 

How often were you doing water changes in their grow out tank? Fish emit a growth hormone that can stunt the growth of their siblings. We have to keep those hormones down with water change. If we don't growth will slow down.

To help fry grow fast and to their full potential we have to feed often and keep the hormones down with water changes. Before I managed to reduce the number of pleco fry I had I was doing daily water changes in their grow out tank. Now I do them every 3 days.

 

How often were you doing water changes in their grow out tank? Fish emit a growth hormone that can stunt the growth of their siblings. We have to keep those hormones down with water change. If we don't growth will slow down.

To help fry grow fast and to their full potential we have to feed often and keep the hormones down with water changes. Before I managed to reduce the number of pleco fry I had I was doing daily water changes in their grow out tank. Now I do them every 3 days.

I started doing them every 4 days but now I do 50 percent once a week

 

I do have one with a deformity. She has a bent spine and is a little smaller. The fish has been eating and swimming fine, so I don’t want to cull, but should I?

 

I started doing them every 4 days but now I do 50 percent once a week

That should have been plenty with so few fish in a 10 gallon tank.

I do have one with a deformity. She has a bent spine and is a little smaller. The fish has been eating and swimming fine, so I don’t want to cull, but should I?

As long as she is otherwise healthy I wouldn't cull her.

 

That should have been plenty with so few fish in a 10 gallon tank.

As long as she is otherwise healthy I wouldn't cull her.

Do you think that I accidentally bred dwarf platys somehow? I also moved the original “fry” to my 10 gallon planted tank to protect the newborn fry.

 

Do you think that I accidentally bred dwarf platys somehow? I also moved the original “fry” to my 10 gallon planted tank to protect the newborn fry.

Any thing is possible. Was your female pregnant when you got her? If she was we can't know if she bred with a dwarf. Since you found a fry we have to assume the originals are now adults and will probably not grow any bigger.

I had some molly fry for a while. Some grew as they should but 2 of them stayed very small. I have one bristle nose pleco that stopped growing at about an inch long. She is about 1 1/2 years old now. She is the perfect size for a 5.5 gallon tank. All this to say. Not all fish grow to the average size for their species.

 

Any thing is possible. Was your female pregnant when you got her? If she was we can't know if she bred with a dwarf. Since you found a fry we have to assume the originals are now adults and will probably not grow any bigger.

I had some molly fry for a while. Some grew as they should but 2 of them stayed very small. I have one bristle nose pleco that stopped growing at about an inch long. She is about 1 1/2 years old now. She is the perfect size for a 5.5 gallon tank. All this to say. Not all fish grow to the average size for their species.

My female is a yellow Mickey Mouse platy and the make is a red wagtail. Both were about 2 inches. She was not pregnant when I bought her. I’m not sure if this has anything to do with it, but I do have a pair of swordtails in the same tank that could have hybridized? Also, will the fish get any more color even if they don’t grow?

 

My female is a yellow Mickey Mouse platy and the make is a red wagtail. Both were about 2 inches. She was not pregnant when I bought her. I’m not sure if this has anything to do with it, but I do have a pair of swordtails in the same tank that could have hybridized? Also, will the fish get any more color even if they don’t grow?

I really don't know. I had mollies for a very short time. I've never had platy's. I decided they were not the fish for me. I love a peaceful tank. They were far from peaceful so disrupted the harmony in my tank. I found them a new home.

 

My platy fry are 4 months old but still, they don't seem to be growing. Maybe they are , very slowly that is. They aren't very active but once I change the water it usually perks them up for a few days. They are still no bigger than 1/2 inch (about 1 1/2 centimeters). They have shown no signs of gender and I'm starting to get concerned their growth is stunted. Is the "A fish won't grow bigger than its tank" true for baby fish? I have 10 fry in a 2 1/2 gallon tank. Is there anything I can do to encourage their growth?

 

They are probably big enough to go back in the main tank unless you have BIG fish in there. My wife tells me that platy fry grow better when adult hirmones are present in the water.

 

They are probably big enough to go back in the main tank unless you have BIG fish in there. My wife tells me that platy fry grow better when adult hirmones are present in the water.

Oh wow very interesting... I have 2 cory catfish and a guppy (with a large mouth) as well as a snail in my main tank (which is a 10g) I fear the fry will get beaten up but I could test it out. Would they grow better if the adults were say... cory catfish that probably wouldn't attempt to kill them? I'm also afraid I wouldn't be able to see them since my tank is crowded with plants and decor. Do you think they would hide like they did when they were first born or would they be more active?

 

Our platy fry are always pretty active but we never take them out of the tank and the adults pretty much ignore them once they can't fit them in their mouths. No guppy gonna fit them in its mouth. Nipped at, maybe, but the should be a-ok. The cories will probably mostly ignore them once they see not food pellets.

 

To get fry to grow fast in any tank they must have fresh water often. In a 2.5 gallon that would be daily temperature matched conditioned water changes. In a ten gallon it’s still an advantage to change part ( 40% ) of the water two or three times.

I know this seems extreme but until you try multiple water changes for oneself in a fry grow out tank I would completely understand anyone who thinks this is hot air.
I did not think it would make as much of a difference myself until I tried it in my ten gallon grow out tanks.

It is said.
Fry release a hormone into water that that stops other fry from growing. This I believe to be true?

 

To get fry to grow fast in any tank they must have fresh water often. In a 2.5 gallon that would be daily temperature matched conditioned water changes. In a ten gallon it’s still an advantage to change part ( 40% ) of the water two or three times.

I know this seems extreme but until you try multiple water changes for oneself in a fry grow out tank I would completely understand anyone who thinks this is hot air.
I did not think it would make as much of a difference myself until I tried it in my ten gallon grow out tanks.

It is said.
Fry release a hormone into water that that stops other fry from growing. This I believe to be true?

Thanks, I can try daily water changes. Any other input on fry not growing because of other fry hormones?

 

DO you have lights on your tank?

 

Like mentioned lots of water changes help a ton. I've heard the hormone thing too, but ive never seen a scientific source cited either. It makes sense to me, but even if it isn't true you need to change lots of water. If for no other reason than water quality because you should also be feeding several times a day for maximum growth.

 

DO you have lights on your tank?

I do have lights.

 

So this is ok? she won't eat the fry?

 

Sorry mygerbilprince, looks like nobody what’s to risk saying the adult fish won’t do what comes naturally.
One option is to add a couple of fry and wait 48 hours before you add any more.

 

I don't know if I want to take that risk

 

If those at the only fry you have alive in the last for months then the adults are eating fry 100% .

Don’t take the risk then.