Sorry to ruin your plans but a 5 gallon cannot support a Betta and at least 5 neon tetras, there is no way. Bettas are aggressive fish and need space, he will feel cramped and could end up killing the tetras. Also a bioload of that much will make you do water changes like 2-3 times a week instead of 1 a week. Also neons if not properly schooled or in big schools, can nip all of the bettas fins off. Overstocking when you are new is definitely not recommended.
pH shouldn't be worried about with bettas, worry about ammonia, nitrite, and nitrate more. pH should stay the same as long ad you aren't buffering it.
pH shouldn't be worried about with bettas, worry about ammonia, nitrite, and nitrate more. pH should stay the same as long ad you aren't buffering it.
