Andy Sager
Aquarium Advice Addict
Do you find 8.2 to be too alkaline, or are you in the "Fish will acclimatize" camp?
Not that I'm passing judgement, obviously you're doing just fine by your fish!
It's a good question that had I not been doing this now, with these fish, I'd have 2 different answers. You see, I have fish that came from different states thereby different water chemistries. For the fish I got up North in VA and NJ, I tried to keep their water at a lower PH as they were being kept up there. ( I tested their water for verification of hardness and PH) Once they were here and growing, I started changing their water to be more alkaline just to make it easier on myself. I was using proper PH 6.5-7.0 and the fish were fine and started breeding in it. I was pulling spawns for fertility verification then due to excessive heat outdoors and again, using the Proper PH treated water, I was having good hatching success. On a couple pairs, I experimented with pure rainwater, which was a very low PH, similar to what they were in when I got them, and had the same results so I assumed that the hatching rates were fish based and not a problem with the water. Now, these other fish came from my buddy down in S. FL where he too was on well water and the water there is a higher PH AND hardness ( take the h2o out of a gallon of water and you could seriously hurt someone if you threw the mineral leftovers at someone lol ) and his fish are doing just fine in my well water. Now all the fish are in my untouched well water and the eggs from all the fish from everywhere are hatching fine. So this is proof ( for a lack of a better word) that they did acclimate to the new water and it's not been a problem. HOWEVER.....
Flash back to 1974, I moved from NJ to S. FL and brought along a trio of breeding angelfish with me. Not realizing the water differences were as bad back then, I acclimated my fish slowly and they survived the move. The problem was they never spawned again. They went from prolific spawners to nothing. I can only assume they didn't adjust the the new water well enough to breed again. I kept them another 2+ years with no spawns then sold them off.
I can only assume that today's fish are just more used to the different waters whereas my fish 40 years ago, were too close to their wild "cousins" and didn't like the change. Back in the 1980s, I had another hatchery and all the angels were in straight dechlorinated tap water and I produced fry with no problems. I can only assume it was because all my breeders were born in the same S. Florida water I was using. Who knows??
Hope this explains it.