Stingray didn’t eat today!

[CaptainAquatics]

Hello all!
Details:
I have two stingrays, Pico (5” BD) & Pine (5.5” Pearl). They live in a 130 Gallon aquarium (will either be upgraded as they grow or they will be rehomed) with a fire eel (12”), 2 Green phantom plecos (~4-5”), and a flowerhorn (~4.5). Water changes are 50-75% every 5 days, 40 gallon sump filtration (170 gallon system).
Nitrate: 10ppm
Nitrite: 0ppm
Ammonia: 0ppm
I had bought a needle nose gar 2 days ago but it passed away this morning (looks like the flowerhorn decided to take issue overnight).

Issue:
This morning when I came down to feed (about 20 mins ago) they were both buried in the sand, not too abnormal. However when I offered food (I tweaser feed) neither would eat. Should I be concerned? They have been eating very well.

Update:
as I was writing this post Pico popped up and is cruising the tank picking up food (I dumped their food in to sit on the ground). Pine is still burried.
edit: Pico just buried again after cruising for a bit.

 

[CaptainAquatics]

Bump - They have stayed hidden under the sand since my last post

 

[Ansorgii]

If its just a few hours I wouldn't worry.

The water likely still has a bad taste to it, just wait 1-2 days until everything is calm again. Who knows how it went down, stingrays can be scared aswell. And sometimes fish just don't feel like it.

 

[CaptainAquatics]

They have been buried most of today. Gonna do a water change tomorrow.

 

[Gpdriftwood]

They have been buried most of today. Gonna do a water change tomorrow.

If a stingray doesn't jump on food immediately something is wrong every time from all my trials and tribulations. I would not house pups w any of those tankmates personally. That also sounds like u have a real potential for too much bio load very quickly. I would be changing about 1/3 water every 3 days probably if I was u. In the time I have been keeping rays I have found that to me they require a drip/trickle system otherwise the maintenance is overwhelming. Definitely do a less than 50% water change and if possible separate from tankmates. Hopefully u get them back to eating soon.

 

[CaptainAquatics]

Did a waterchange last night at like 1am - about 45%. Both rays were swimming around by the end of it. Woke up a few mins ago and one ray was hiding but the other was swimming around. Be sitting watching her for like 30 mins but I startled her when I moved too fast and now she’s buried again.
I’ll update when I try to feed them today.

 

[Reese11]

Did a waterchange last night at like 1am - about 45%. Both rays were swimming around by the end of it. Woke up a few mins ago and one ray was hiding but the other was swimming around. Be sitting watching her for like 30 mins but I startled her when I moved too fast and now she’s buried again.
I’ll update when I try to feed them today.

That was good you went ahead and did the water change even being so late. It’s a good sign to see the one swimming around, I would agree with Gpdriftwood about more frequent water changes and I would keep an eye out for any aggression towards them from any of your fish, sometimes it all happens at night and we never see what’s happening. I would also try feeding at different times of the day or when you see them most active and try to vary their diet and mix it up for them

 

[CaptainAquatics]

So to give an update…
About 30 mins after feeding Pico (the stingray that came out and ate) buried again and has been like that since. Pine (the other stingray) did move around a bit after I dropped food in but buried again quickly after (and still is).
I’ve changed their water change schedule to be 30-40% every three days and will likely do another water change either tonight when I get home from work (I work until 11pm) or tomorrow morning.
I have primarily feed them cut up raw shrimp (like from the grocery store) that I keep frozen and dethaw as needed. I got them some raw tilapia and offered it a few days ago (actually that was offered the day before they started doing this…), but they both spit it out and rejected it so I’ve stuck to frozen shrimp.

I haven’t personally seen any aggression from any of the fish (primarily watch for the flowerhorn) but I am wondering if he’s giving them issues when I’m not around as he has been getting more aggressive with the plecos.

Two buried photos were taken just now, then I attached a photo from a few days ago.

Some more relevant info is that I just got Pico about 2 weeks ago and Pine I got a week ago.





EDIT: The minute I posted this pico came up and started swiming around

 

[CaptainAquatics]

Pico went back into hiding shortly after my last message. Any ideas why they might be hiding so much? I know they usually do because of stress but I can’t think of anything that’s changed in the tank the last few days except for the addition and passing away of the gar

 

[CaptainAquatics]

Update: Did another water change last night. Today when I came out they were both swimming around. I prepped their food and offered some. Pico ate right up and swam around for a while after, Pine ate one piece then hid (where she still is). Pico went into hiding shortly after eating but then came up and started swiming again not 2 minutes later.
I’m starting to wonder if maybe there is something wrong with the food that’s bothering them? It’s fairly old shrimp (leftover bag from a few months ago that I’ve been finishing off with them - been frozen the whole time), and I just take it, thaw it in a bowl with warm water, then chop and feed.
Today They finished the last of the old shrimp so I’ll see if moving to the fresh bag I bought makes any difference.

ATM starting to get quite worried about Pine, this is day three of not/barely eating for her. Pico seems to be doing mostly better.

I also don’t want to rule out the idea of parasites, although I don’t / haven’t seen any evidence of that I want your guy’s thoughts.