How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Category: Pet
Satisfied Customers: 2457
Type Your Pet Question Here...
A new question is answered every 9 seconds

How will overfeeding kill goldfish

This answer was rated:

How ill overfeeding kill goldfish? I have had 5 goldfish die in the last week, 3 of them were young. There do not appear to be any grey or white spots on them, the only thing I can think of is overfeeding or something I am not aware of

How long has your tank been up and running with fish in it?


How many gallons/litres of water does the tank hold?


How many fish were/are in the tank?


How many times a day and how much food were you feeding the fish?



Customer: replied 8 years ago.
We have had the tank (bowl) for about six years with no problems until now. The bowl holds about about 250Ltrs and there would be at least 9 fish left (there are now 6 casualties). I have been feeding them once a day, decent size pinch of flakes. I have been taking care of the fish whilst my mother is overseas and nothing else has changed with their environment other than the person feeding them (me). I have not fed them for 2 days as there appears to be enough floaties in the water for them to feed on. My brother has had a look at one of the deceased with me and it appears to be in good shape, no marks or anything unusual. He has done a ph test on the water this morning and it is not acidic but alkaline. Like I said the only thing that has changed is their regular feeder. There are a number of young ones in the tank as some of the adults were breeding last year. What do you think?
Customer: replied 8 years ago.
I have had a sample of water taken to a local pet shop and they have done 4 water tests - ph, amonia, nitrate and another one and they all came back normal. Could it be a temperature issue as we have had some rather cold overnight temperatures in the last week or two?

There are a few possibilities here.


The water temperature could have fallen to a dangerously low level which in turn would have caused fish deaths.


Overfeeding--when you mentioned that "there appears to be enough floaties in the water for them to feed on" it's a sign of overfeeding as the general rule of thumb when feeding fish is to feed only an amount that the fish will be able to consume within 3 minutes.

Uneaten food in an aquarium begins to decay thus causing water problems.


You mentioned that water tests had been done but didn't mention exact results.

Ammonia should always test at ZERO. If any amount of ammonia was detected on the test kit it would indicate a major problem.

Nitrates should have tested 40ppm or lower although if they tested a bit higher would not indicate a dire emergency.

No mention was made if the water was tested for Nitrites but they like ammonia should also always test at ZERO. They too are lethal like ammonia.

An ph range of 7.0-8.0 (alkaline) is fine for goldfish.


In my experience I've found that when sudden and rapid fish death occurs it can almost always be traced to a water quality problem as a result of the presence of ammonia and/or nitrites in the water or an external toxin that has entered the water.


Best wishes and please let me know if you have any questions.





Customer: replied 8 years ago.
One last thing - there are 3 different water plants in the pond, a water lily and your normal lily pads (which are small plants) and another plant that has gone rather rampant in the pond - also the normal oxygen weed. I have been in touch with my mother who has suggested to cut back the rampant one as there is alot of foilage and roots. Would too much greenery be an issue?

Actually a lot of foliage provides extra oxygen and consumes nitrates which are the end result of the breakdown of harmful ammonia and nitrites.


So I think that in order for the foliage to be a problem it would have to in some way impede the fish's ability to swim.



TROPICAL FISH AFICIONADO and 2 other Pet Specialists are ready to help you