I have a Nanocube HQI 28 gal tank, running almost a year. This is my first tank and I have not had a problem like this so far. I have 2 ocellaris clown fish (1 orange, 1 black), a royal gramma, a diamond goby and various hermit crabs and snails. The last fish we added was the gramma a few months ago and everyone was doing fine. All 4 fish would swim together at feeding time and all had a healthy appetite. I came home yesterday from work and noticed my clowns especially acting strange. They usually "greet and follow" us when ever we are near the tank, but instead they would hover in the back of the tank under some rocks. Our goby was also laying near them with his mouth open the whole time. When I tried to feed them last night, none of them came out to eat when before they gobble the food up. I checked my water last night and ammonia and nitrite were 0, pH 7.8 (low I know), nitrates 60 and spec gravity 1.025 temp stable around 79F. I had completed a water change 3 days before. I went ahead a did 8 gal water change last night and now the pH is back to normal and nitrates at 30. Today my clowns are laying right next eachother under the same rock in the sand. The black clown did eat a little bit of the food that came to him and my orange one did not eat. This is just very odd behavior coming from usually very "social" fish. Also, if this information helps, I've noticed our clowns trying to host our frogspawn over the past week or so and our gramma has been displaying "aggressive" behavior toward them (opening his mouth very wide) when they are hosting. Do you have any idea what could be going on? Could they be mating? Could the frogspawn have stung them? Like I said, I've only had a saltwater aquarium for around a year and have never had anything like this happen. Thank you!