Hi guys,

So I'm conducting an experiment where I'm using a blocked ANOVA and have a few questions about my data set. I'm looking at the abundance of a species of fish over different habitat types. I have 3 treatments (habitat types; each is a 3x3 m square - I'll refer to them as my plots) and 3 blocks. Each block has 1 of each treatment. So 3 plots per block and 3 blocks total so all together I have 9 plots (each treatment has 3 plots). To collect my data, I set up GoPro cameras at each plot to observe fish. I'm watching the videos and record which fish I see and how long they stay within the view of the camera.

Now, my question, is it okay to use more camera footage from one block than another block? For example, one time when I collected footage, one of my cameras died early. 8 of my plots have 2 hours of footage each while 1 only has 1 hour of footage (the camera that died early was in block 2). Does that mean that I can only use 1 hour of footage for all of my plots? Or can I use 2 hours of footage for the cameras in block 1 and block 3 and use 1 hour of footage for all of the cameras in block 2? In other words, for cameras 1, 2, 3, 7, 8, and 9, I will use 2 hours of footage and for cameras 4, 5, and 6 I'll just use one hour. Is it okay if all 3 treatments have an equal amount of time recorded, but the amount of time recorded from each block is different?

So, in a nutshell, is it okay if my blocks have an uneven amount of time recorded as long as my treatments have an even amount of time recorded? Or do all my blocks have to have an even amount of time recorded to use?