Hi All, The instructions said to be thorough, so here's my attempt at thoroughness: Parameters using API Master Test Kit: Ammonio, Nitrites and Nitrates: 0 pH: 7.4 I have a 5.5 gallon tank that started out as a fry tank for both danio fry that I found by sheer luck and ghost shrimp fry (larval stage especially). When the ghost shrimp thrived and the 2 danio fry as well, I turned it into a (mostly) shrimp tank. I had to set it up in a hurry because mama shrimp's eggs were looking ripe. I used the foam block from my existing Aquaclear 20 filter in my original tank plus some of that beneficial-bacteria-in-a-bottle stuff. In addition, the plants all came from the original tank. That's how I cycled it on the quick. I honestly can't remember how long it was until I put the mama shrimp in. I know i put the danio fry in right away because they had been sitting in stagnant nasty green water change leftovers for probably 2 weeks until I noticed the "black splinters" and wondered what are those? bugs? It started bare bottom with a sponge filter and then a corner filter was added a few weeks later as it seemed the partition in there was not allowing good flow. It now has an Aquaclear 20 (as of last week), which is keeping the water awesome. I had some poly-filter that I had bought for my other tank, so I cut some off and stuck a block (probably 1/2" x 1/2" x 1-1/2" or maybe smaller) next to where the bubbles escaped the corner filter, and it turns really brown in just a week, so not sure what that means exactly as it could be humic acid, tannins or just lots of organic waste. I added Carib Sea Instant Aquarium as a substrate a few weeks ago. It has water conditioners and such in it already. No rinsing required. This all began mid February. The first danio was discovered around mid Feb and the second a week behind him. The ghost shrimp were released late February. I intended to move the 2 young danios in with my other 5 danios as soon as they grew a bit bigger. I ended up with probably 15-20 shrimp plus a few adults I already had, and then I gave 2 away last week. Another batch of shrimp were released 2 days ago, but I'm not sure any of them are left. Time will tell. The tank is well-planted. It has 2 mats of java fern that I got 6 months ago along with several new ferns that I've attached to rocks and coir. I just got two more plants, but I'm not sure what they are. One is a bunch of stems and is likely a waterwort or another -wort of some kind. It won't stay down despite two plant anchors and is dying. I need to figure something out. The other plant I got has broader leaves and is rosette style with actual roots. Nice healthy green. Oh, and some floating java moss balls. I figured they would be good for the larval shrimp. As for a light, it is sort of impromptu because I was in a hurry in the beginning, but I think it works well. It's a desk lamp intended for use as a "happy light" or for beading/knitting/etc. It is 27 watts and 6500 on the spectrum? I had it on randomly, usually in the morning and then at night, but I just got a timer and it's set to be on 8 hours total in a split. The danio fry ended up being from 2 different "litters" because one is full zebra, and one is a mix of zebra and LF leopard, although it looks just like LF leopard. I only know it's a mix because my only 2 males are zebra. I feed a combo of brine shrimp flakes, sinking pellets, baby bites powdered fish flakes, frozen baby brine shrimp, and frozen mysis shrimp. Usually once a day. So, I hope I didn't leave anything out. The problem is this: yesterday, almost suddenly (so it seemed), my older juvenile danio (zebra approx. 2 months old) started swimming funnily (alternating between stillness and twitching, swimming in circles, tail only curled one way, swimming like he's freaking out, and he is not eating. I am not sure if he is physically capable of getting to any food. After several hours and a water change, I took him out and put him in a tupperware container just in case it was contagious. The younger LF leopard was doing fine. Because it was all by itself at this point with a whole bunch of ghost shrimp, I went ahead and moved it into the main tank. I actually floated her (I really have no idea the sex) in a container for a bit and forgot about her for an hour, and she managed to jump in herself. Funny since it's a Fluval Edge, as she could have easily landed on top of the glass or on the floor! so, i did a search for this problem and even found videos on youtube of similar behavior, but they all said it was due to old age because apparently danios tend to develop a spinal curvature at the end of their short lives. However, my danio is only 2 months old. Could it be imbreeding? Ammonia poisoning? I do water changes about twice a week of 10-25%. I was using Stress Coat as a water conditioner, but I started using Prime last time because I read it was good for beginning tanks. Shrimp are ALL fine and unaffected by anything as well as other danio.