Is it safe to add prime to a tank with fry ?

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Mofo fish

Exodon
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Feb 13, 2021
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May sound a bit silly but I know fry can be a bit delicate. I want to top off the tank with fresh water and I usually do about a half cap in my 90 gallon that my festae bred in. Is it safe to add prime or stress coat ?
 
Yes it is safe as long as you dose appropriately. If you are just topping off the tank, you will need to figure out how much you need to dose based on the amount of new water you will be adding.
 
Fry are very delicate and normally kept in small tanks to concentrate first foods so it's bad practice adding unknown water to their tanks. Tap water can vary unpredictability beyond chlorine/ chloramine.

Most fish breeders use proven water from an existing tank for fry. In my case, 10% volume of a large breeding tank is sufficient to replace 50% of 80 fry tanks.
 
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Yes it is safe as long as you dose appropriately. If you are just topping off the tank, you will need to figure out how much you need to dose based on the amount of new water you will be adding.
Ok it’s a 90 gallon and it’s down about 2 inches. Usually takes about 2 5 gallon buckets to raise it to the level from before. I’ll dose for 10 gallons
 
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Fry are very delicate and normally kept in small tanks to concentrate first foods so it's bad practice adding unknown water to their tanks. Tap water can vary unpredictability beyond chlorine/ chloramine.

Most fish breeders use proven water from an existing tank for fry. In my case, 10% volume of a large breeding tank is sufficient to replace 50% of 80 fry tanks.
Interesting, I started a different thread and basically everyone said to let the parents raise them. They are red Terrors in a 90 gallon aquarium
 
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Interesting, I started a different thread and basically everyone said to let the parents raise them. They are red Terrors in a 90 gallon aquarium
If I was you.. I would make sure the fry have a lot of small places to hide in case the parents decide to eat them.. and once they are bigger, pull them out and put them in their own tank. That's just my opinion. I'm sure you'll have better luck growing them if you pull them, but personally I wouldn't bother.
 
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There are at least a couple different concepts/ways to raise fry, and all have equal merit.
Raising in a smaller grow out tank where food is easy to get can be advantageous.
Allowing parents to raise fry also has certain advantages (fry can munch on the parents slime coat providing extra nutrients, and passing along some immunity).
I have done both.
If with parents in a large tank, I use a pipette or turkey baster to send food directly into the shoal of fry.
I will often siphon off half the fry to a grow out tank, just in case there is an anomaly in the large tank.
There may also be need for a number of grow out tanks as the fry grow, many grow at different rates, and separating by size keeps large fry from eating smaller ones.
And there is a point where they need to be separated from parents, because the parents may want to spawn again, and the older fry then, become a threat.
 
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Fry are very delicate and normally kept in small tanks to concentrate first foods so it's bad practice adding unknown water to their tanks. Tap water can vary unpredictability beyond chlorine/ chloramine.

Most fish breeders use proven water from an existing tank for fry. In my case, 10% volume of a large breeding tank is sufficient to replace 50% of 80 fry tanks.
There are at least a couple different concepts/ways to raise fry, and all have equal merit.
Raising in a smaller grow out tank where food is easy to get can be advantageous.
Allowing parents to raise fry also has certain advantages (fry can munch on the parents slime coat providing extra nutrients, and passing along some immunity).
I have done both.
If with parents in a large tank, I use a pipette or turkey baster to send food directly into the shoal of fry.
I will often siphon off half fry to a grow out tank, just in case there is an anomaly in the large tank.
There may also be need for a number of grow out tanks as the fry grow, many grow at different rates, and separating by size keeps large fry from eating smaller ones.
And there is a point where they need to be separated from parents, because the parents may want to spawn again, and the older fry then, become a threat.
I went out and bout a 10 gallon kit I’m going to set it up now. I will try and grab about half. I have a 20 and a 55 lying around that I will eventually find the spirit to set up for them. Is it safe to top off the water with prime ? Only clarifying with you because let’s face it you clearly are the most trusted source being an administrator and having years of experience. Thanks I’m advance !
 
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I use a dechlorinator whenever adding chlorinated (chloraminated) water to any tank, fry or not.
I would not bother if using rain water, or unchlorinated well water)
With the dose measured to treat the amount of water added.
All dechlorinaters main ingredient is a salt called sodium thiosulfate, or calcium thiosulphate)
Most often sodium thiosulfate because its less expensive.
To be realistic, if the tiny amount used (in comparison to the volume of water in the tank) kills a few fry, they probably were too weak to make it anyway.

I do not however just top off fry tanks.
I do the regular water changes I would normally do on tanks, fry or not (am just a bit more careful with temp, and siphoning).
 
The only issue you’d run into with prime is it using up the available O2 innthe water column if you overdose.

I routinely do 10-20 percent water changes on fry tanks without adding anything dechlorinating. And do 30 percent on adult fish But I also have a significant amount of organic material in my tanks which immediately neutralizes the chlorine anyway. I honestly do not have anything to treat my tap water with. I have no prime, stresscoat etc.

the issue you’re going to run into in your new ten gallon fry tank is that it will be very very “sensitive” easy to foul, easy to crash becuase it’s new. Old water from an old tank doesn’t help- it’s only value is on the Lawn or garden. Old filter media can / does help. But even then it doesn’t replace the host of organisms growing on the glass and substrate of a mature tank.
Also consider that 90-95% of new world cichlids are better at raising fry than you and I are and it’s often better to just let them do it with your assistance in the form of adding fry food with a baster or dropper for the first few weeks.
 
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