So I thought I'd share an experience with the community. Around midnight I decided to clean the shrimp tank nothing special just a small Vac and 10% water change. Same old routine except I didn't wait long enough for my replacement water to hit room temp, the difference didn't feel like much so I went for it. After nearly 10 minutes went by I notice about 8 of my shrimp pulling a shawshank. My colony is about 100 strong and they seemed fine, but here I am with these guys and gals trying to climb past the water line. I start to get nervous when I see that number hit 20. I test all the parameters and everything is normal likes it's been for months. The temperature in the tank was 2 degrees higher then normally (usually 70). I figured that this had to be an oxygen issue. I never thought I'd really use chemistry but oxygen doesn't diffuse well in higher temperature water, essentially the hotter the water the less oxygen it has. I grabbed some ice cubes, shut down the lights, turned a chop stick into a temporary pull up bar and waited. Those 20 shrimp slowly dwindled in numbers. Not one got to the rim of the tank and they all seem to have chilled out. They even climbed back down into the water after a visit to the surface. No deaths, just some odd behavior.