the recipe called for 25 grams but that is all grain is it any different if im only doing a partial
I take it you mean for the southern cross....yes, it will be different, because in an AG beer, the boil volume is > than the volume going to fermenter, it reduces down and concentrates. So the BG will be different. And the original recipe is for 50L
The bittering will specifically depend on the actual boil gravity, which will depend on the efficiency of the mash...so what you will need to do is take a sample of the boil, cool it quickly in the freezer, and take a grav reading to be sure.
Then, using the gravity of the boil, and the volume of the entire batch, enter the hop schedule in a calculator such as
here. Unfortunately it is in yank weights, just convert using google. Or search for other calculators. If the boil gravity is only a couple of points under/over, its not going to make a lot of difference. If it's more, it will.
Easiest thing to do, though, would be to download a trial version of beersmith, and enter the recipe there. It has a 21 day trial, so if you do your brew within this time, you can adjust the specific hop weight 'on the fly', once your actual boil gravity is known. And it so happens that I've been working out the details in beersmith, so I could post up the recipe file so you wouldn't even have to type it in. :lol:
If you change my earllier advice and sparge with 8L instead of 5L, this should give you 13L into your pot for a boil, with the 250g ldm it will happen to give you 1049 for a boil gravity....but that will vary, depending on how well the mash went, so it will need to be checked. But if it's on target, you would need 17g of southern cross flowers (11.9%AA) for 60 minutes, and 40g saaz (4.0AA) for 20 minutes. Typically, if the target isn't hit, you might need to adjust the 60 min addition by a couple of grams either way, to rebalance it. In beersmith, thats very easy to do....I won't explain how at this point, because without having beersmith on screen to look at, it wouldn't make a lot of sense.