lost a snail

Zebra nerite in my main tank died. I'd had it almost a year- two months shy...

Several days ago I saw it lying sideways in the back of the tank, against a plant stem. I put it in the front of the tank right-side-up, and it climbed up the wall a few inches but then stayed motionless in that one spot on the glass for a day. Found it the next morning upside down on the substrate again. I flipped it upright and left it there, to keep an eye on it. It didn't move for two more days. This morning I realized it was dead when I saw the kuhli loaches trying to get under it- probably they were trying to eat it. I lifted it out and the smell was not strong, but the body came out so yeah, it is gone.

I tested the water- Ammonia was 0.25, Nitrite 0 and Nitrates 40. I did a ten gallon wc.

I'm feeding the kuhlis betta pellets soaked in garlic today, in the food trap. Cherry barbs are getting little bits that float out through the air holes when the food disintegrates and the kuhlis dart around. Waiting for one of the striped kuhlis to go in, then I'll add a few bites to the trap again. Albert looks normal now, has gained his weight back. The thinner black kuhli is looking a bit better, but Snaky Fish is still very thin, although active.