No, its true you are overstocked, but not by a terrible amount. The Plec, especially if its a common plec may be completely wrong as they can grow to be huge. You may need to look at pictures of plecs (here on TFF there should be some, or google images) and attempt to identify it and then discuss it with the members here. The way you size a tank for yourself is to do a bunch of homework: you hunt down the technical descriptions of all the fish you potentially want to stock and then note the maximum size they grow to, as stated in the descriptions. Then its simple multiplication of the numbers of each species you hope for and that will give you a total stocking in inches. The rough guideline that's good for beginners (people with less that 3 years active experience or so I'd say) is one inch of fish to 1 US Gallon of usable tank water volume.
Note the the job of actually working out your final stocking is a good bit harder than just these max stocking guidelines, as there is another phase where you consider what shoal sizes minimum are recommended for each species and then finally you have to also crosss-consider each species against each other species with respect to compatibility for living in the same tank together. There are also aesthetic considerations such as having examples of bottom-dwellers, mid-swimmers and surface-swimming fish within a community tank if a community setup is what you're going for.
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is it healthy for 7 fish (which includeds 3 platy, 3 small tetra, and a plecostumos) to all live together in a 5 gallon tank or is it to crowded? If it's to crowded what should I do other then getting a bigger tank? PLEASE HELP!
