When doing an AG brew we would adjust our mash and sparge liquor prior to the mash and then measure the PH of our mash wanting it to be somewhere around 5.3, this aids mash reaction, hop extraction etc. It's the grains that give us the acidity we want and providing the buffering capabilities of our initial water are not too high (We adjust as above if required) the grains will do this for us.
The Alpha acids from the hops are used for Bitterness and not for a reduction in the PH of our wort.
On a further note I did a nettle tea yesterday with 20gm of nettle tops and 400ml of water boiled for 30 min
I ended up with 100ml of nettle tea which was of a green colour and cloudy consistency. Although the nettle is related to the Hop plant (Cannabis plant as well I found out) the actual tea, which was very nice to drink it was not very bitter, nor did it have a very strong aroma. At least none that we could use. I would say had more of a malty taste to it and using that component it maybe usable but not in the way I had hoped. It would be easy to do a beer with nettles but not a nettle beer.
I have some hope of using the green liquor and have now put it aside in a glass bottle to see how well it will fine down and what colour the resultant liquid will be. My thoughts are that if used in a very light summer beer the addition of the nettles will give a green tinge to the pale beer which would be acceptable similar to the gimmicky "
Sign of Spring" brew. Investigations however show that nettles were in distant past used with stouts or dark beers. Was this because they only had access to the smoked brown malts at that time

Very tired last night but moving down the path of a smoked nettle beer which we would have to use Bavarian Smoked Malt which as far as I know the only smoked malt still available I came across this very interesting article. Seems now I have two brews to do. One a light beer and one a dark beer.
Barliman's Best
I also found an artical discussing Hall and Woodhouse's "Stinger" and it mentioned in the artical that it is dry hopped with Challenger, Target and Styrian Goldings" the first bit of concrete information on the light beer. Whislt I may not know the specific quantities or If I will even use these specific hops the info that "Stinger" is dry hopped it interesting in itself.
The Nettle and the Damage Done
Anyway off to order me some Rauchmalz
Cheers