Float your fish in the tank for 15-30 minutes so the temperature of the water in the bag matches the temperature of the water in the tank. Then, add your fish to the tank, but don't add the water from the bag to the tank water.
In a bladder-tank, you can only "read" the pressure TANK residual with the water off and the tank empty of water, leaving only the air-pressure in the top portion. If...
Platies are usually pregnant between 6 - 8 weeks. Once you notice that your platy's stomach has a \___/ shape, then you know she is due to give birth soon....