So, hardness unknown, if you don't have the test solution you can get it online from your local water company.
Your PH is just a tad too high, the temp is too low though handleable for them(I almost forgot they have a pretty good range of temps they can handle from 68-80 degrees or so, so you should be within safe ranges for him at least, the pacu needs it no lower than 72F though), and there is far, far, far from enough space in there, even with youngsters, as again the redtails need 300 gallon tanks minimum, they grow fast and need the space to do it in, your other fish also require much larger tanks.
Water parameters for the Redtail should be: pH 5.5 - 6.8 Temperature : 68°F - 82°F (20°C - 28°C) Water Hardness : 5-10 dGH. And obviously ammonia, nitrite and nitrate should be zero, nitrate is tolerable in small amounts...Tank size needs to be bigger. They really do best in large ponds, not tanks. =(
Bala sharks also get over a foot long, like groups, and need a huge amount of space. I suggest you downgrade on your fish, at least on the catfish, or upgrade to a very large pond.
Someone almost tricked me into getting one of those, but I did some research and said no way. They get so big! And are aggressive and very high energy.