Question:

I am interested in buying a ro unit.i have just started up with a tropical fish tank do you need any additives or anything to add to the ro water.

Answer:

I am not a tropical fish man myself but I do know that with a tropical system you must add buffers back into the water to maintain the hardness. The amount added will be determined by the biotope that you are trying to simulate.

Buffer powders are readily available from most good aquatics retailers.

For marine systems you do not need the buffers as this is added by the salt.

Hope this helps