Want to know how to raise your adorable goldfish fry into healthy adults?
You’re in the right place today!
I’m going to share what I’ve learned in my own breeding experiences to help you take your fish from an egg to a healthy young juvenile goldfish.
Keep reading to learn more…
Steps to Raising Goldfish Fry: Stage by Stage
Stage 1: Eggs
You want to get the eggs out of the parent’s tank ASAP – or get the parents out.
Let them incubate at temperatures between 68-72 F.
Incubation temperature influences the sex of the fish (source).
At higher temperatures, more males are produced.
Too low and you will get more females.
Fertile eggs will start getting a little curved black line (the spine of the baby) attached to two black spots (eyespots).
Watch carefully and you can see the babies change positions inside of the egg!
Unfertile eggs turn opaque and fuzzy.
Those should be removed.
Add snails in with the eggs.
I do this for several reasons.
- They eat uneaten food off the bottom
- They can eat fungused eggs
- They make the nitrogen cycle more efficient, resulting in cleaner water
- They are harmless to the fish
I use young ramshorns for this.
Some people also use shrimp to deal with unfertilized eggs.
If you have a lot of unfertilized eggs, it’s likely because you either:
- Hand-spawned in too large of a container (especially using the Traditional method rather than Chinese)
- Have an infertile parent
- Or the eggs were kept too close together and not spread out properly
Stage 2: Hatching to 2 Days
When the babies first hatch, you will see a tiny eyelash-like object hanging on the side of the aquarium.
They literally just hang out, not doing much.
Look closely and you can see their eyes are shiny and glowing-ish… and a little bit creepy looking!
Once in a great while, they may try to swim by madly darting from one place to another.
At this stage, they don’t have developed mouths.
So no point in feeding!
They are still absorbing nutrients from their yolk sack.
At this time, water quality is an issue that should be addressed early.
Baby goldfish are very sensitive and can’t stand ammonia.
The more you start feeding them – the more waste they will make (fouling the water).
Some people will use an airstone and perform frequent water changes.
Some people will use a sponge filter.
I don’t like the current (or the workload) of either of those methods.
Baby goldfish are so tiny and fragile, and I strongly believe do better with less water flow.
So I have found that for me, my favorite method is live plant filtration.
I may add an airstone turned down to where it is barely producing little bubbles to prevent low oxygen levels at night, and situated near the surface (this may not even be necessary, depending on stocking density and the type of container).
But the plants purify the water and offer small microorganisms for the fry to graze on.
(They do need a light source.)
A fantastic fry plant is Elodea, because it does not need a substrate…
… Meaning you can literally throw it in any tank…
… And it purifies/oxygenates the water wonderfully.
Here’s another FREE tip.
When changing water/vacuuming the bottom, use a piece of airline tubing as a siphon with or without (preferably with) a bit of netting rubber-banded over one end.
Anything bigger can be too powerful and suck up fry.
If you accidentally suck up a fry?
Use a turkey baster to transport them back.
Stage 3: 3 Days to 1 Week
Once the fry start “free swimming” they are ready to eat.
Now they won’t be hanging on stuff.
They kind of inch/scoot around through the water in a jerky way looking at things and maybe biting stuff – they are hungry and hunting for some grub!
At this point they need food right away.
This begs the question:
After several experiments, I’ve learned some foods are good, some not-so-good to use.
Baby brine shrimp 2-3x per day is the best place to start.
Their bellies will turn pink!
Avoid overfeeding though.
You will want to feed them by gradually increasing the amount of food.
(At this point you can also raise the temperature to 74-78F to speed up their growth rates – though it’s not necessary.)
It really doesn’t have to be a big deal or take up a lot of space to raise baby brine shrimp for them.
Read More: What to Feed Baby Goldfish Fry
Stage 4: 2 weeks to 1 month
Your babies are starting to look more like goldfish.
In spawns of fancy goldfish, you will be able to spot the single-tails around 1.5-2 weeks.
Most breeders get these ones out as soon as possible.
Fused tails will be evident.
You’ll also start seeing the differences between calico’s and metallics.
Calicos start looking a bit pink or lavendar with whitish areas (some are mostly pink).
Many calicos will have black eyes (button eyes).
Metallics stay brownish but get shiny scales on their sides, bellies, backs and heads.
Their eyes will stay normal.
At around the 2-3 week mark, you can begin offering gel food along with the brine shrimp and gradually transition them over.
Break up the food into little pieces and distribute around so the big ones don’t hog it all! 😉
They will be more reluctant to eat anything but the baby brine shrimp, but keep giving it to them and reducing the brine shrimp.
It’s part of the “weaning” process!
My favorite food to feed my fry at this stage is Repashy Super Gold.
It has so many great ingredients for them and has high protein.
Stage 5: 2 Months to 4 Months
It can take several months before your adorable little goldfish fry start “coloring up.”
You’ll also be able to notice more defects as the fish get larger.
The fry will require heavy feeding to develop deep bodies.
You’ll now need to think about finding homes for all the little fishies!
Troubleshooting Common Problems
Flukes can be a big problem in fry tanks.
They can literally wipe out your population in days.
Flukes are usually transmitted from the parents’ tank to the babies.
You will initially notice their gills may be open, that they hover near the surface of the water, gulp at the surface or scratch on things.
Sometimes you can actually see the flukes hanging from their chin like a beard.
But there’s a problem:
Fry are very sensitive to medications.
And most of the ones that won’t hurt the fry won’t hurt the flukes either. (I won’t tell you which ones I’m thinking of, but they’re Prazi and formalin-based medications.)
The best solution to this problem?
Stop the flukes in the parents BEFORE they get to the babies.
That’s why I treat all my fish – including breeders – with MinnFinn.
And I have never had a problem with flukes in my fry because of this treatment.
You can try treating fry with it, but you will want to test it on a small group before doing it to the whole batch just in case it’s too strong.
And you’ll want to use the regular (not double) strength dose.
Feeding the wrong kind of food can lead to the water fouling too quickly.
Overfeeding can also lead to problems internally in the fish.
This can be suspected if it’s just a fry or two every so often rather than mass deaths.
Some believe it’s normal to find a dead fry now and again.
Not all are born strong enough to survive.
(Maybe that’s why goldfish have so many babies?)
Runts can be present in pretty much any spawn, regardless of what you do.
But some things can favor the developing of runts.
Usually, it’s not enough food or not spreading the food around well.
I hate to say this:
But sometimes the fish are just dumb. 😛
They aren’t as good at noticing food as their siblings, or spend too much time hiding when they should be hunting.
But that doesn’t change the fact that they are still cute as a bug’s ear!
Personally, I like the runts.
Not all goldfish have to be whales.
Raising goldfish fry is a fun and rewarding process for hobbyists.
Being able to see them from birth to a full grown fish?
So what about you?
Have you ever raised any fish babies?
Let me know in the comments below!