Newbie, is this a disease or just them having fun?

My Molly is swimming around my log, swims normal and is active. When I first got them the blacker one was the first one to eat, now he kind of just hangs back and waits for it to fall and the whiter one sat back and waited. But now they've totally switched. Then I caught them doing this last night and thought it was just them fooling around until I came home from work today and saw the blacker one doing it again. Also noticed some vertical swimming head up, not very often. Should I be concerned? I have a video on my iPhone but don't know how to up load it. Hard to describe without the visual if any one can tell me how to upload that would be awesome!

 

First of all. Welcome to the forums.

As for uploading video. I think you will need to upload it elsewhere ((like youtube)) and then link it

What are your current water parameters?

 

This is the video link.
Tank readings are
p.h-7.2 ammonia-0ppm nitrite-0ppm nitrate-5.0ppm

 

Thanks. From that video, and the perspective, just looks like they are playing in the bubbles. My Danios and one of my neons do it all the time. One of the danios if the bubbler isn't running ((have been keeping it off lately to help lower my PH, read somewhere it would help so trying it)) if I walk near the tank and look in he will start bumping the bubbler till I turn it on and then he will play in it. and then my neons will go play in the currents it creates

 

I'm not familliar or experienced with mollies, but that looks like they are just enjoying the current from your bubbler that carries them up, and they go down around the log to catch the flow again and again. quite cute to watch actually. Hopefully there's nothing wrong with them.

 

It could be that they're just glass surfing. A few of my fish did that when I introduced them to my tanks, but they stopped after a week.

Looking at your parameters, your pH may be a little low. I remember watching videos about fancy mollies and him saying that the fish prefer a pH at around 7.5, a minimum of 7.2.

Mollies also require hard water. Do you have a gh/kh test kit? Most tap water in the US is hard, though.

 

They have been in for 1.5 weeks now. I don't have a gh/kh kit. I did add stuff to bring the ph down to 7.0 as being told by my local fish store. But after reading about them I'm going to do a PWC this weekend because I was obviously miss guided. I read that I should leave the ph alone because that's what my water contains and that's what I'll be using from the tap. It's usually around 7.4-7.6. There is also 3 red platys in the tank and they're thriving. Any input on the natural water oh level?

Also thanks for all the quick responses, you guys are awesome

 

That PH is just fine for the mollies and platys

 

Your tap water's pH is perfect for livebearers such as mollies, platies, swordtails, etc. I'd recommend never using the 'pH down' junk, as it's just going to cause pH swings, which kill fish.

 

Ok so my second source was right, thanks guys. Made me sleep easy last night.

 

I used pH Down in my tank, and it also negatively affected my KH, causing my pH to become unstable. I was advised to do several water changes to get the stuff out of the water. (Just sharing in case it helps you.)