The phrase "tried testing" is correct and usable in written English.
You could use it in a sentence like, "The engineers tried testing various materials to find the best solution."
He'd tried testing it in his hotel room by firing it into a mattress.
When I first tried testing this theory, I approached a girl in a club, only to leave her mid-conversation to return to my friends.
"We've tried testing again and again, and it hasn't worked," said Jesse Hagopian, a teacher at Garfield High School in Seattle and a leader of a group of teachers who are boycotting a test typically given in January.
I tried testing the search on the show Smallville.
The first time I tried testing out the phone I was in my apartment, which gets notoriously awful AT&T coverage.
His tried, tested and focus-grouped lines.
His methods are upheld, the soundness of his approach tried, tested and proved.
She declared that the relationship was "tried, tested and — yes — special".
This was a tried, tested and slightly tired theme that was nevertheless deftly dealt with.
It is a tried, tested and cost effective model".
Some VPN providers are better than others: tried, tested — and trusted — by security professionals.
