I'm seeing something I can't understand about my goldfish.
I have a ten gallon aquaponics tank. About a week ago, maybe a little more, I noticed my goldfish were gulping at the surface a bit, and my water was a bit thick & very foamy. I deduced low O2. I added some bits of twine to my main filter to divert water so it streams out onto the surface and agitates to help with O2 levels (see my pics on profile to understand what I mean). Saw a change by the next morning. Water didn't seem as thick, foam all gone, plants & fish seemed very happy.
Now I still notice my fish (who don't look stressed otherwise) still coming to the top and "drinking" from the surface water. I don't see them forcing air bubbles through their gills, unless they try to "eat" a big bubble on the water. I was worried, and confused, that it was O2 again, but there are no other signs.
I just tested my water - I should add I do have another 2 weeks until my tank can be considered fully cycled - everything is literally perfect. Total harness, alkalinity, and pH are right where I want them, no trace of nitrites or nitrates, as I expected from the system. Do you think my goldfish just want to eat when they see me? They are voracious little buggers, ate all my azolla in less than a week. Maybe they think there will be food whenever I'm around? The tank is in my room, and they do follow me as I walk by and crowd in the corner where I'm standing (actually a little creepy, LOL) Just curious if anyone has seen this before when there are no O2 issues. Like I said, every other behavior/aspect of fish/tank/plants seems normal to me.