Water bubbles on surface, only in this particular tank

[frogdance]

Any idea why the water surface would appear like this? This only seems to happen in this tank. I have used smaller plastic tanks and never saw any bubbles. This larger tank I see this problem.

[Lacibeth]

Standard questions: what type of water are you using (tap, spring, etc.)? Are you treating it with anything? If so, what? Have you tested it to see what pH, nitrites, nitrates, etc levels are?

[frogdance]

Standard questions: what type of water are you using (tap, spring, etc.)? Are you treating it with anything? If so, what? Have you tested it to see what pH, nitrites, nitrates, etc levels are?

I use spring water. I do not treat it. I don't have a filter so I just bought a tank with one.

I tested the water. It is a bit hard. It was high in amonia, so I am changing the water.

But the bubbles will appear after just a day or two of changing the tank.

My PREVIOUS tank never had this happen.

[Lacibeth]

What's the water temp? My random speculation is that the water is warming causing the dissolved gases to come out of solution and something has increased your surface tension holding the bubbles there. It's odd that your larger tank would bubble not the smaller so perhaps not a change in temp, but an increase in gas production due to bacteria.

[John]

This is usually caused by an increase in organic chemicals in the water (byproducts from the metabolism of animals and the breakdown of waste food). I would give it a water change.