Hi
I believe there has been some misguidance to the actual volume of water this item can hold??
I see someone said it would hold 2.5 gallons, well thats incorrect.
The volume of a sphere measuring 11x11x5.5 inches = 696 cubic inches
696 cubic inches = 2.5 UK gallons
As this item is only half a sphere, the maximum it can hold is 1.25 uk gallons. That would more than likely end up being less than a gallon, bearing in mind you cant fill it to the top. Also, it may not even be half a sphere, but could be less depending on the angle of the sphere sides?
That size is in no way acceptable for any aquatic animal let alone a betta that may grow to 2 1/2 inches long. I find it very disturbing that moderators on a large fish forum would say it was acceptable without working out the size correctly?
You are correct, it is, after looking closer, a half sphere. I did the calculations based on it being a 5" thick disc, which on further examination it is not. Thank you for the clarification, as well as the mathematical calculation of the volume.
That converts to a hair over 1.5 US gallons, probably closer to 1.25 once reasonably filled. Per my previous links to documentation, still good enough. Personally I wouldn't use it, just due to the wall hanging aspect.