Turtles/Painted turtle won't eat
My painted turtle will not eat. He/she (not sure of sex but always call it him) is about 3 inches, kept in a 40 gallon tank with an African side neck turtle(about 5 inches). They each have their own docks. Their water is always 77-83 degrees(check very often). They have a huge heavy duty filter also. I noticed Theo stopped eating 2 days ago. I tried giving him his veggies then his shrimp then his store bought turtle pellets but he smells it and swims away. He has no interest in eating. I'm not sure if it's because of my side neck but there has never been a problem before. I clean their tank every 2 weeks. My light is 60 watts. I use water from my tub but always make sure to put cleaner in it. I havent cleaned my take since Friday. I haven't changed anything in their environment, I thought he could possibly stop eating because winter is right around the corner but I don't know for sure. I also have 2 water heaters. He is doing everything normal, still swims and basks a lot just stopped eating
How long have you had your turtles? I have some ideas, but without more symptoms it's really hard to say what the problem is.
1) Your tank is too small. It's big enough for the painted for now, but not for both turtles together. You need a much larger tank, or separate tanks--figure 10 gallons of tank per inch of turtle. If the filter can handle double the tank's capacity, it's probably adequate. Water quality is really important, which is why even with a good filter you don't want to crowd the turtles.
2) The water is too warm. Even the sideneck doesn't need water over about 77 degrees, and painteds like it a bit cooler. As long as there's a good basking area of 90-95 degrees, the water doesn't need to be too warm. If there isn't enough difference between basking and water temps, the turtles may not bask enough, resulting in skin and shell issues.
3) You don't have a UVB bulb. This is really important, and can affect appetite and behavior over time, and may eventually lead to serious bone and shell deficiencies. I'd recommend getting a ZooMed Powersun 100 watt. It will provide both heat and UVB (change yearly).
4) Changes in light can affect some turtles, even when housed indoors. Some are more sensitive to this than others--in my experience wild caughts more so than CB. You can try increasing the number of light hours by 2-4 hours to see if that makes a difference.
Don't worry too much at this point. A couple of days without eating isn't major with turtles, and if he's still active that's a very good sign. Really sick turtles are generally lethargic. Let me know if anything changes, if you notice any other symptoms (especially anything like lopsided swimming, wheezing, yawning/gaping, etc.), or if you have any other questions.