german blue rams

im think they would be fine in those conditions as long as you acclimate them well. my tap water is VERY hard but my ph is around 7 and my GBR's have been doing fine. biggest thing is keep up on water changes to keep clean water in your tank and i think you should be fine.
 
ive found the best way to get my discus acclimated to my home aquarium is to float the bag in the water in the tank for about 20 min to get the temp. to match, then after that, about every 8-10 min., pour a little of your tank water into the bag and repeat until the bag is pretty full. (im sure u know this next part but ill say it anyways) then just scoop the fish out of the bag and stick it in ur tank or pour the bag of water out over a net, catching the GBR in the process and putting him in ur tank.
 
my water is like yours if not worse, all i did was float the bag for an hour adding water every ten minutes. they did get a small case of ich but i treated straight away cleared up in no time. so id say try 2-3 hours floating the bag adding water every 20mins.

after you put them in keep a close eye out for any whitespots, if you dont get to it quickly it can be very hard to treate.
 
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