I am going to go against the grain here. Since you have not bought your horse yet and you do not know what type of horse you will have, I suggest you make a more sturdy fence than one strand of tape.
This fits into the category of 'just because it worked does not mean it is what you should do'.
I would recommend three strands of electric. I think of what is offered, tape is probably the safest.
You need one strand low enough to prevent those horses that like to reach under from just scooting under the fence. You need one strand high enough to discourage the thought that jumping out is an easy option. Then one strand in the middle to fill the large void.
If you are going to go with wire, coated wire, or electric rope be sure to install them properly. Improperly installed they can be very dangerous.