Tilapia Fingerlings Deaths

[RikuzaYuzu]

Hello,my dad started keeping some red tilapia at the back of his house.

He said that his fish started dying one by one like a day or two ago,and he didn't do anything particular.My dad uses a pump brought online and also a filter with lava rocks and some other things inside as filter media.

He bought about 50 of them and 5-6 of them died

Can someone tell me what's the problem? And i can't give pictures or videos right now since my dad is outside.

 

[Lajos_Detari]

The first thing you have to check is the ammonia and nitrite levels which can kill the fish.
How long has he set up the filters?
How big is the pond or tank?
How big are the fish?

Filter will need at least 1 to 1.5 month for it to have enough beneficial bacteria to remove the ammonia and nitrite unless you used some bottled bacteria or established filter media from other tank.

You can read about tank cycling or nitrogen cycle from internet to understand this.

Cycle Your Tank! A Complete Guide For Beginners

Fishless cycling https://www.fishforums.net/threads/cycling-your-new-fresh-water-tank-read-this-first.421488/ Silent or plant cycling https://www.fishforums.net/threads/planted-silent-cycling.470400/ Fish-in cycling...

www.fishforums.net

The tank/pond need to be big enough to support 50 fish.
The filter or filters also need to be big enough to support the big number of fish (but provided the tank/pond is also big enough).

Secondly, bacteria like Columnaris will also kill the fish fast especially in a crowded tank/pond.

Diseases of Tilapia - An Introduction

Tilapia is native to Africa and the Middle East. A decade ago, few people knew much about tilapia. Today, it has emerged to become the second biggest aquatic species group after the carp group, with a…

thefishsite.com

A few other basic questions:
1) Did he use water conditioner for his tap water?
2) Did he overfeed the fish which can also cause high ammonia.
Also, make sure that he didn't use any detergent or chemical to wash his tank, buckets for his water, etc.

To solve ammonia and nitrite problems, the quickest solution is to do large(70% or more) and frequent(example: daily) water change.
This will remove and dilute the ammonia and nitrite level.
Also, cut down on feeding.

 

[RikuzaYuzu]

The first thing you have to check is the ammonia and nitrite levels which can kill the fish.
How long has he set up the filters?
How big is the pond or tank?
How big are the fish?

Filter will need at least 1 to 1.5 month for it to have enough beneficial bacteria to remove the ammonia and nitrite unless you used some bottled bacteria or established filter media from other tank.

You can read about tank cycling or nitrogen cycle from internet to understand this.

Cycle Your Tank! A Complete Guide For Beginners

Fishless cycling https://www.fishforums.net/threads/cycling-your-new-fresh-water-tank-read-this-first.421488/ Silent or plant cycling https://www.fishforums.net/threads/planted-silent-cycling.470400/ Fish-in cycling...

www.fishforums.net

The tank/pond need to be big enough to support 50 fish.
The filter or filters also need to be big enough to support the big number of fish (but provided the tank/pond is also big enough).

Secondly, bacteria like Columnaris will also kill the fish fast especially in a crowded tank/pond.

Diseases of Tilapia - An Introduction

Tilapia is native to Africa and the Middle East. A decade ago, few people knew much about tilapia. Today, it has emerged to become the second biggest aquatic species group after the carp group, with a…

thefishsite.com

A few other basic questions:
1) Did he use water conditioner for his tap water?
2) Did he overfeed the fish which can also cause high ammonia.
Also, make sure that he didn't use any detergent or chemical to wash his tank, buckets for his water, etc.

To solve ammonia and nitrite problems, the quickest solution is to do large(70% or more) and frequent(example: daily) water change.
This will remove and dilute the ammonia and nitrite level.
Also, cut down on feeding.

Well,to be short and quick since one more fish died,he only started the filter for only 3 days and says he has lava rocks and other rocks as filter media,then he says the fish eats everything,btw it's fish pellets,the pond is about 2m x 1m x 1m,and my dad said the tarp he used to make the pond has been throughly washed

 

[RikuzaYuzu]

Well,to be short and quick since one more fish died,he only started the filter for only 3 days and says he has lava rocks and other rocks as filter media,then he says the fish eats everything,btw it's fish pellets,it's about 2m x 1m x 1m

and sorry,i think i'm suppose to be saying fingerlings,since it's about the size of a finger or bigger

 

[Lajos_Detari]

Well,to be short and quick since one more fish died,he only started the filter for only 3 days and says he has lava rocks and other rocks as filter media,then he says the fish eats everything,btw it's fish pellets,the pond is about 2m x 1m x 1m,and my dad said the tarp he used to make the pond has been throughly washed

Just tell him to do large water change frequently if he suspects high ammonia or nitrite.
Some example of large water change:
If ammonia level is 1.0 ppm, changing 80% of water will reduce it to 0.2ppm.
If ammonia level is 0.5ppm, changing 70% of water will reduce it to 0.15.
Change the water to reduce ammonia to 0 and observe the fish.

All the filter medias (lava rocks, etc) will need 1.5mths to have enough beneficial bacteria.
Did he rinse the lava rocks well in case they carry some pollutants.
What filter is he using? Brand, model, size or flow rate?
Usually each filter is rated by tank size.

 

[Lajos_Detari]

Whenever you are unsure, just do a large water change to dilute any ammonia, nitrite, toxic and reduce any pathogens (bacteria, parasites) that can kill them.

Bacteria and parasites multiply very fast in warm water.
By doing large water change, at least you can reduce their numbers.

Next, observe for any symptoms on the fish before they die.
Look for any fast breathing, white spots on the body, any reddish colour on their bodies or other abnormalities on the bodies, fins, tail; any clamp fins, gills opening wide, etc.
You may have to read about fish diseases from the internets as there are too many.

 

[RikuzaYuzu]

Just tell him to do large water change frequently if he suspects high ammonia or nitrite.
Some example of large water change:
If ammonia level is 1.0 ppm, changing 80% of water will reduce it to 0.2ppm.
If ammonia level is 0.5ppm, changing 70% of water will reduce it to 0.15.
Change the water to reduce ammonia to 0 and observe the fish.

All the filter medias (lava rocks, etc) will need 1.5mths to have enough beneficial bacteria.
Did he rinse the lava rocks well in case they carry some pollutants.
What filter is he using? Brand, model, size or flow rate?
Usually each filter is rated by tank size.

Well,my dad's gettieg irritated for me asking so i just told him to do frequent water changes,the filter was bought online and not sure myself. My dad is someone stubborn and likes to do things his way most of the time so i hope he listens

 

[RikuzaYuzu]

Whenever you are unsure, just do a large water change to dilute any ammonia, nitrite, toxic and even reduce any pathogens (bacteria, parasites) that can kill them.

Thanks for the advice so far! Hope i can save my dad's tilapia.

 

[Lajos_Detari]

Thanks for the advice so far! Hope i can save my dad's tilapia.

I edited my post.
Please read the additional info.

 

[Lajos_Detari]

Sorry, I realized that since they are fry, it may not be advisable to do large water change.
I think its better to do smaller water change like 30%, but do it more frequently.

Also, fry are delicate, weaker and more difficult to care.
You will need to wait for them to grow up and build their immune system.

The next thing your dad must really observe is for diseases.
In a pond or big tank, you will need large amount of medications to treat them and this can be costly.

So, prevention is always better than cure.

 

[Colin_T]

Besides a probable water quality issue as mentioned by @Lajos_Detari, you could get your dad some aquatic plants for his pond. Like a house warming gift for his fish They will help reduce nutrients and floating plants will shade the water to help keep it a bit cooler. If the plants do well, your dad can sell some of them and use the money to buy fish food or more fish.

Make sure there is some aeration in the pond and plenty of hiding places for the fish. You can glue lengths of pvc pipe together to make fish hiding places.

And big regular water changes will help keep things cleaner until the filter is established. Good luck