Uhhh. Wow. Interesting debate.
I 100% completely agree with everything P45 has said.
Don't screw with water paramaters unless your spawning, or have completely out of range water for what you are keeping.
I do agree that you should buffer your water, to keep your pH from falling. Crushed Coral usually solved the problems, but be careful. Sometimes certain crushed corals can have 'orthophosphates' binded to them, in which they release a high amount of phosphates in your water. With the right combination of tap water, orthophosphates, and lighting, you could have some VERY serious green water algae problems. A customer of mine had this issue, and now she is forced to either use water from her brothers house down the road, or a constant supply of Phos-X.
Consistancy is key. Too many people 'screw' with water paramaters, which creates a rollercoaster effect with each water change. The fish hate this way more then the uncomfort of being in a pH range that is slightly out of the 'ideal' paramaters, found in the wild.
Too many people fuss with RO Units, Buffers, yada yada yada.. When the key is adapt your fish to your water source, so you can make large frequent water changes. The fish are WAY more stressed from lack of proper water quality, than they are if the 'ideal water parameters' are somewhat out of range.
Obviously, African Cichlids shouldn't be kept in a low pH by any means. However, most soft-water fish can adapt to high pH, without too much trouble. Some are MUCH more sensative than others, such as Wild Discus and Wild Apistogrammas. I often import wild Stingrays, Cichlids, and Tetras directly into a pH of 7.6-7.8, with no problems.. However, Discus and Apistos, as well as a few other fish are a different story.
It's interesting to know that my PetSmart has a main system with shared water quality.. Everything from Killies and Tetras, to Mbunas and Aulonacaras are kept on the same water source. How come they thrive in such an 'un-optimal' environment? Because PetSmarts system has an automatic water change system which never allows the Nitrates to climb above 20ppm, and the water quality is CONSISTANT. I spawned many fish in PetSmarts tanks while I was working for them, and unfortunetly I got in trouble for intentionally breeding the fish. I spawned Convicts and Firemouths, in the same water that I spawned Red Zebras and Kenyi's. Wowie, If I would of tooken KUTTY's info, that would be impossible. Because fish that are 'just surviving', usually don't breed.. The breeding is usually done by fish that are 'thriving..' Right?
So Kutty, you tell me.. How can I import wild fish directly into a pH of 7.8, and have no issues? Especially with a fish as sensative as a Stingray? Also, if you were so 'absolutely correct' about the advice you give, you would know that not ALL African Rift Cichlids MUST have a pH of exactly 8.5. It was my understanding that only the lake tanganyika cichlids enjoyed a super high pH from 8.2-8.8? While most of the Victorian and Malawi water parameters range from 7.6-8.2, and 7.8-8.4? I guess I could be a know-it-all and jump down your throat for posting bad information.. But then again we are just hear to gather the opinions of others to make our own, not to get scientific evidence from any schmuck who has the ability to type.
Miles