Is this "floating" ...?

I could need some advice about my axie. He is most of the time hanging around just below the surface, and I understand this is usually not a good thing.

But I don't think the symptoms match the "floating" symptoms I've read about, hence I wonder what it may be, and what to do?

This has been going on for at least five days. Earlier he was often by the surface, but at least sometimes down at the bottom, Now he is always by the surface.

This is how he behaves:
He hangs just below the surface, I can see small movements all the time (tail, or leg, or gills; he is not completely still for long periods), and he also changes position every now and then. Sometimes he is in one corner of the tank, then he swims leisurely to the front window and hangs there for a while before swimming to another place. When one comes into the room he often swims to the front glass.

I should say his "normal" position is A in the drawing at Image - TinyPic - Free Image Hosting, Photo Sharing & Video Hosting, occasionally he is down at B, and sometimes in between. C is rare, but happens. (I don't have a new photo of him, could fix it tonight)

He does not seem to have any problems moving, and the belly/tail is more often pointing downwards than upwards.

We have always fed him by the surface, he has never eaten on the bottom. He eats fast and poops about twice a week.

Background info:
* Have had him for a year, he is about 20 cm.
* Tank size 72 litres (about 60*35*35 cm, water to the top).
* plants, stone and wood from the pet store, light 20 W, sand as substrate.
* Temperature 20 degrees C or slightly cooler. (I have an effective usb-fan to cool the surface if the day temperature gets too high),
* We give him one small/medium sized earthworm every two days. He eats fast and without problems. Poops about twice a week, size maybe 1.5-2 cm x 8 mm, solid.
* Waterchange about 30 % once a week.
* Large inner filter, circulates 350 litres/hour, no currents (the surface is completely still apart from the waves of the fan)

I have plenty of axolotls who choose to hang subsurface, some more than others, its more common in tanks with plenty of surface plant cover. The fact that you feed him on the surface may encourage this behavior. As long as all your water peramiters are ok and it is showing no signs of distress (such as shooting around the tank) I wouldn't be concerned.

Sounds normal to me! Some axies just like the surface. And 'problem' floating is usually characterised by the tail end floating rather than the head end.

I do have a question though - do you have an airstone or bubbler? Sometimes axies prefer the surface because there is more oxygen in the water. If not you could try one - I have an air curtain that my axies like to play in - they swim into the stream of bubbles, ride it to the top, then float down.

And you could try feeding him on the bottom of the tank, just to see if he WILL go down to the bottom, and it's a choice to be at the surface rather than a problem.

I think you only need to worry if he appears distressed, such as trying to swin down and then floating back up with no apparent effort.

Agree with the two previous posts - and also, if he's fed at the surface he'll probably spend more time there, it's probably his version of 'begging!' (Mine 'beg' on the floor).

Thank you all - I think you're right, he seems just fine still. Just got a little worried