R/O in Freshwater: necessary or not?

[cmwalters]

Basically what the title says. Is reverse osmosis necessary in freshwater? I use conditioned tap water in all my tanks and I have never had a problem. Albeit my tap water is not terribly hard or toxic.

 

[flitabout]

Not at all. I have stupid hard water so I do use a 50/50 mix. If my water wasn't so hard I wouldn't use RO/DI at all.

 

[20cc]

pure propaganda

 

[cmwalters]

I could see where it would have its advantages. Like if you were trying to keep a species that had very specific water needs, you could customize the water to your needs. I would like to have a RO unit, but I was trying to weight the benefits and downfalls.

 

[J.Mcpeak]

Basically what the title says. Is reverse osmosis necessary in freshwater? I use conditioned tap water in all my tanks and I have never had a problem. Albeit my tap water is not terribly hard or toxic.

Then you are lucky. This is a multifaceted answer, I've used RO in freshwater for 8 years, to control water hardness and to some extent algae, though I'm not sure how effective that is against algae, pure water has no food for algae. If you want proper soft water fish or someday marines, you will need one, or you will need to keep buying water. They pay for themselves in no time. Tap water is never a constant, you never know what you are putting in your tank. I usually mix RO and re mineralize with tap to a specific hardness suited to each tank. Water hardness controls alkalinity and in turn pH. So I vote yes.
Edit-sorry I meant 6 years, I've kept fish 8 years.

 

[Rivercats]

I have my own unit and have used RO water off and on for 30 years depending on what I want in an individual tank. Most tap water is fine. I always suggest taking a reading of ammonia, nitrites, nitrates, phosphates, ph, gh, and kh just so you know what your reading are (but you can often get a report with this information from your local water company). If your tap is fine and your not keeping any special species then there is no reason to use RO. You can use RO as either a sole water source and remineralize it or you can use RO to cut with tap water to lower specific levels listed above. I have tanks I use it to cut with tap water and some tanks that only use tap water.