Rainwater From A Butt

[IAN_Tanglin]

I am starting a new 63 litre tank for tropical fish. The tank is set up based on tap water, with Aqua Safe etc. This is still slightly turbid after 24 hours - so I have added an extra fine filter. What worries me is the KH reading which appears to be off the scale.

I have an existing small tank - 17 litres, I have used same water source and readings have been fine. However, I need to upgrade to add to the fish colony. I have added discard water from the small tank and rinsed the foaom filters from the old tank in the new tank - to help with the N2 cycle.

My question is: since I am in a very hard water area, Surrey UK, should I have started with rainwater from a butt. I have plenty available, but obviously it is cold. Before introducing any fish, should I now start changing the water and gradually introduce rainwater?

Has anyone tried this? Are there any problems associated?

Thanks for your help.

 

[xhan]

I don't think it will make a huge amount of difference, you can get things to reduce water hardness - but harlequins and guppies don't tend to mind too much - they haven't so far?

 

[OldMan47]

A lot depends on the fish that you want to keep Ian. If they are like my typical livebearers, you do not need to add any rainwater to dilute things. If you go more to the South American type fish that like a low mineral content and low pH, the rain water is a good idea. I use rain water for my cories but most of the other tanks get tap water with a high mineral content.

 

[BigC]

I utilize a mix of Rainwater and Reverse Osmosis water for my tanks.
ATB
C