Why is my platy failing to thrive?

About 3 weeks ago I bought an adult sunburst platy and added her to a ten gallon tank with 3 other variegated platies and a docile male betta. She has seemed depressed and disinterested in food since day one. All she does is hide and she wont come out to eat unless I add minced garlic to the food...even then she might eat one or two flakes at most. I feed vegetables a few times a week, she has no interest whatsoever. I thought at first she was pregnant but she has no gravid spot and is very thin. I've been doing water changes every 2 or 3 days for over a week now just in case, but my water tests fine...no nitrites, no ammonia, nitrates barely register on the test, and all the other fish are just as active and hungry as ever. Nobody in the tank bullies anyone. I've watched her closely while still (she's always still) and no worms are poking out of her butt. She has no ich or outward signs of infection. I'm at a loss! I'm buying a 45 gallon tank this friday and was planning on eventually moving my platies into it and getting a few more, but don't want to introduce any sickness to a new tank. If anyone has any ideas, I'd appreciate it.

Also, the other 3 platies and the betta I have had since December, didn't buy and add them to the tank when I bought the platy in question.

This is a picture of her just now.

@Colin_T is our disease expert hopefully he can help

Maybe she is frightened of the betta. Even though he is not attacking he is still "there" and may be releasing pheromones into the water.

Can you post a picture of the entire tank?
Can you make a short video showing all the fish and then the platy?

Gah it wouldn't let me upload it directly to here no matter how short a video i made, so I used imgur. Funny I caught HER being a bully.

Naughts said:

Maybe she is frightened of the betta. Even though he is not attacking he is still "there" and may be releasing pheromones into the water.

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I suppose it's possible she's afraid of the betta, even though he completely ignores them. My hope is to move the platies to the big tank and let the betta have the ten gallon to himself.

Just to show how nice this betta is though...this is an older picture when the babies were still growing up...he would literally sleep with them. If the problem is just fear it is all in her head, but I hope that's all that's wrong and she'll be fine when I get them moved. It's frustrating seeing a fish be so miserable and not knowing how to help.

The platy is definitely stressed.

Add some floating plants like Water Sprite. This will provide the fish with more shelter and can help them feel more relaxed. If the Water Sprite grows too much you can plant it in the gravel.

Have a picture on the back of the tank to make them feel more secure.

You can upload videos to YouTube and then copy & paste the link here. We can visit YouTube to watch the video.

Does the Betta always pace up and down the front of the tank?

Alright, stress I can try and fix. Buying hella plants when I get paid this weekend. The betta doesn't always pace, only when I'm standing right there. He wanted fed for sure. Half the time he just goes from spot to spot taking little naps.

Colin_T said:

The platy is definitely stressed.

Add some floating plants like Water Sprite. This will provide the fish with more shelter and can help them feel more relaxed. If the Water Sprite grows too much you can plant it in the gravel.

Have a picture on the back of the tank to make them feel more secure.

You can upload videos to YouTube and then copy & paste the link here. We can visit YouTube to watch the video.

Does the Betta always pace up and down the front of the tank?

Click to expand...

I appreciate you taking the time to help me out.

hobostu said:

Alright, stress I can try and fix. Buying hella plants when I get paid this weekend. The betta doesn't always pace, only when I'm standing right there. He wanted fed for sure. Half the time he just goes from spot to spot taking little naps.

Click to expand...

No probs, he has you trained well.

Good plants to try include Water Sprite for the floating plant, and Ambulia, Hygrophila polysperma and narrow Vallis to grow along the back and sides. If the Water Sprite gets out of control you can plant it in the substrate where it will grow into a lovely light green shrub.

I went ahead and took my betta out of the tank. He's stuck in a one gallon until I get my new tank and get it cycled, which sucks, but I don't want the platy to starve. Her ribs are visible now. She's still hiding but she DID come out and eat this morning after I removed Carl, so that's good.