Yes I am sorry but none of those fish should be in that tank.
theres 4 neons
two glow lights
a guppy
Two glass cats
and a pleco
Neons and glo lights should be groups of at least 6 each and need tanks that are at least 10gallons, probably 15gallons would be more like it. They need room to swim around, being small shoaling fish.
Guppy,
could be ok but it's not something I would do.
Glass cats, get too big for that size of tank. A tank that size would not allow them room to grow and could risk stunting.
Plec, no way. Sorry, even if it's a smaller species of plec they create too much waste to be in anything less than 30gallons IMO. If it's a common plec, they get to 18". In that tank it will be stunted and also your water will be terrible soon, if not already.
Add to this the fact that it is a hex tank, this means that it is taller rather than longer and means there is less surface area to oxygenate the water.
I am sorry but you have real problems. What size is your other tank?
I hope the krib is ok.
Dana