"honestly I don't test my water so I just filled it up an emptied it a bunch of times I was planning on only having cheap fish in there
if I get anything more expensive I will purchase a test kit"
Sorry if i sound rude or anything...but that is not a good answer bud. Sometimes there are unknown circumstances in aquariums and it causes fish to die, it does happen....but when you know that there could be a problem before introducing stock, why risk it? test kits are not very expensive(and its something you should have in general). Just because a fish is not expensive doesnt mean it should be a test dummy
By the way, cool background...have wanted to do something similar since the first DIY background i saw