There are several ways to tackle this. Sounds like you're moving towards one already. But a couple of things to consider here. InkBird is highly recommended because they work, I've had mine going on 3 years, not a single hiccup. If you have a problem, it's probably either a faulty unit, or something is going on with your wifi connection. I have mine running on a 2.4GHz/5GHz mixed network without issue. Changing your heater to a Wifi Heater may not fix the issue if it's your wifi connection. Also, the placement of the controller which houses the wifi antenna is key. It should not be behind the aquarium where the aquarium is in the direct path of the Wifi controller to the Router supplying the Wifi... The signal won't pass through the aquarium with enough strength left over to keep a stable connection. This will be true of any wifi device you get for your aquarium.