Using RO water for my cichlid tank

[waynecav]

I have always used RO water for my reef. Due to my mains water having nitrates of 40ppm I am constanly battling algae in my cichlid tank and would like to use either RO or RO/Tap water mix.
Can you give me some advice on what I would need to add to:

RO on its own

RO/Tap water mix

In order to make it suitable for my cichlids.
The tank is a 50 gallon bow front with a mix of malawi/tang cichlids. The tank is around 2 years old and usually runs at a PH of 7.8 - 8.0

[Tech Support LK]

I can tell you what you need for RO water, but I cannot tell you exactly what you will need for tap water because I do not know the water quality of it. To use RO water for an African Cichlid tank, to keep the pH around where you are currently, you will need to add Malawi/Victoria Buffer. The directions on the bottle are for RO water. You will also need to add Cichlid Lake Salt in order to restore the GH. You may also choose to use Cichlid Trace in order to provide the proper trace elements that these fish require. I think you will find that even using a mix of RO and tap water, you will need to add these products still, just in different proportions.