Iridescent Shark Not Eating

[fishlover2020]

I have pair of Iridescent shark for past 8 years in my tank, yesterday after adding pair of mollies and ballons iridescent shark are not eating the food and swimming only at the bottom of the tank. They are swimming actively but not eating.
 
55 gallon tank.

 

[the_lock_man]

First of all, a message to all members. The subject of iridescent sharks in home aquaria has caused much controversy in previous threads. However much we advise the OP about the potential damage caused to these monster fish, it is their choice to do what they like, whether they take on board our advice or not.
 
The moderation team will not tolerate any lack of courtesy between members.
 
Now then, Fishylover2020.
 
Can you advise what size tank the fish are in, and do you know the levels of ammonia, nitrite, nitrate and the pH of the water in your tank?

 

[fishlover2020]

Tank size is 55 gallon.
 
I dont know about water levels as my thermometer not working from last 1 week.

 

[the_lock_man]

I didn't ask about temperature - I would like to know about the parameters I mentioned.
 
It could be that the additional fish have caused the ammonia or nitrite levels to rise to unacceptable levels - you ought to have a test kit to measure these. It'd be a good idea to get hold of one, you can get them from Ebay, Amazon, etc.
 
I think it's more likely that they are just suffering from being in a tank that is too small - at 8 years old, they should be bigger than their tank by now. Have a read of the blue link in my signature area.

 

[Cat king]

Hi guys , let me firstly say I've kept monster fish for over 35 years now and would say that I totally agree with the lock man as your tank is completely inadequate to keep iridescent Catfish and you should of been told in-store about size and care aspects but as usual and unfortunately it's all about the money and not the fish, I've kept at one point or another almost all types of monster Catfish but let me warn everyone out there thinking of keeping iridescent ( pangasius) Catfish PLEASE DON'T unless you can house them in a tank or pond around a thousand gallons at least, let me give you an example , 18 months ago a neighbor knocked and asked could I take a couple of her fish as they were moving house I agreed as I have spare tanks , she brought them over I looked in the bucket and low and behold there sat 2, 5" inch pangasius cats, I put them in my 150 gallon tank that was 18 months ago now I have 2 20" eating machines that I moved to my 2500 gallon indoor pond , so the moral of the story is do your research properly and if possible don't give shops your hard earned money on fish that 1 should not be for sale and 2 will outgrow your tank almost over night, hope this helps, thanks

 

[Colin_T]

Hi Cat King and welcome to the forum

The information you provided probably won't help in this case because the thread is from 2013

 

[Cat king]

Yeh my bad didn't see the dates till ide posted but never mind it might help someone at some point that sees it. Thanks Colin

 

[vlg888]

Hey Cat King, just saw your post and wanted to ask about my iridescent shark, I've had him(?) for 32 years he is about 3 1/2 feet long in a 300 gallon pond. All of his levels are good except nitrate it's a little elevated and I'm working on getting it lowered. will this cause him to slow his eating and how long will he live?