Using Water, Debris, and Hardscape from Rivers

[CwFisher]

Soooo  what's the deal with using river water/rocks, driftwood, debris, silt, media for cycling??...I live on a nice river here in northern California.. Full of trout and a type of bluegill, also two fatty salmon runs a year and huge steelies! The water is good and clean. Been drinking it 30years..I waz at the river, fishing and waiting on my new 20gallon to cycle (done the normal way)and got to thinking...anyway I'm new so any info would be great  stay healthy.    Cw

[Yanni]

I don't think there's really is a problem with using driftwood or rocks out in rivers and things like that. The problem is that you don't know if the river has parasites or some weird bacteria. You can definitely collect the rocks and driftwood but I would try to boil them just to be safe. If the water is drinkable, you can probably get away with just adding the rocks and stuff into your tank. 

[gardenman]

The likelihood is that any driftwood, rocks, etc, you buy came from such a river so no real harm in using it. I just wouldn't count on them being wildly effective in cycling a new tank. A natural river can have lots of other factors controlling the ammonia and other levels that aren't in a tank. A piece of driftwood in a river may have far less beneficial bacteria on it as there's likely a lower fish concentration and less ammonia available to feed it and more things competing for what ammonia is available. We may have a piece of pothos in our tanks to suck up excess nutrients. A river may have a whole grove of willow trees doing the same thing. By the time any water gets to the driftwood/rocks those willows and other trees, or other factors, may have cleaned up all of the ammonia leaving no food for the bacteria you're hoping is on the driftwood/rocks.  With no food for the bacteria there's no bacteria that survives. We tend to view things like ammonia, nitrites, and nitrates as problems. In nature, they're more viewed as fast food with lots of potential consumers fighting for them. 

[RockMongler]

As @gardenman says, that stuff is probably great for you to collect and use in your tank!  It just might not have as much BB as we need in a fish tank, because nature gets significantly higher turnover of water in a stream environment compared to what our tanks get (see, the volume of your tank, vs the volume of a stream, and the amount of water flowing those systems). The biggest worry is possibly bringing home parasites or diseases. 

Only thing I'd worry about is making sure its legal to collect where you are looking!  If you are on USFS land (US forest service), you can 100% collect rocks.  Plant matter can be a different animal, and I am not as familiar with the specific rules there.

[FriendlyLoach]

Yeah, I would just boil it for a while.