Freshwater vs saltwater nitrifying bacteria.

tyler1503 · Apr 15, 2017

Hi R2R!
A couple of months ago I started curing some live rock in freshwater which I suspected had bound phosphate in it. I cured it in a 10gal with some freshwater plants to help take up some phosphate. I know it's not the ideal way to help cleanse the rock, but it's an experiment I was wanting to do. I'm always looking for different ways to do stuff!
I wasn't getting anywhere near the phosphate readings I was expecting and eventually had absolutely no algae growth even after weeks of no water changes. Now here is my first mistake. At this point I should have dried the rock out and let it bleach in the sun. However, in my super excited state I (without thinking ahead) added the rock directly to a newly set up and completely empty marine tank.
So my question is, will the nitrifying bacteria that now colonises that rock survive the change from freshwater to marine conditions?
Of course I plan on doing the initial cycle properly and not cutting corners, this is just something that piqued my curiosity and I couldn't find any information about this online.
Im wondering if I should expect some changes in ammonia testing at all? Perhaps a larger spike when all the freshwater bacteria dies off, or maybe a smaller spike or none at all if the bacteria can survive?

94Roarge · Apr 15, 2017

If the bacteria does die off, it can help feed the new bacteria at least! I think. Maybe?

billw · Apr 15, 2017

I cured my pukani that way, changing water every three days or so. I never had any measureable ammonia while cycling my 350G system. I did see a nitrite peak. I theorized that in changing water every 3 days, I never gave the cycle a chance to complete.

Myka · Apr 15, 2017

Martin Moe discovered in the '70s (I believe it was) that switching nitrifying bacteria back and forth from freshwater to saltwater only damages the bacteria by about 30%. I'm not sure how he came to that number, but my own experimentations have come to the conclusion that switching the bacteria back and forth from freshwater to saltwater damages them "very little". If I'm looking to kill off attached corals or something on live rock, I'll toss it into RO water in a tub with a powerhead and let it percolate for a week, then I'll do a 100% waterchange with RO and salt it up over 2 or 3 days, and taking just that short period of time, I don't see any blip in ammonia. Works well.

tyler1503 · Apr 16, 2017

Awesome. Thanks everyone!
Do you have a link to that information @Myka ?
It's now day 3 and I don't think there's any ammonia at all at the moment. If it makes it to a week without any signs of ammonia, I'll add a frag and see how it goes!

Myka · Apr 18, 2017

tyler1503 said:
Awesome. Thanks everyone!
Do you have a link to that information @Myka ?
It's now day 3 and I don't think there's any ammonia at all at the moment. If it makes it to a week without any signs of ammonia, I'll add a frag and see how it goes!

Now that I'm actually physically looking for you so that I could quote it, I realize the book I have in mind is Conditioning, Spawning and Rearing of Fish with Emphasis on Marine Clownfish by Frank H. Hoff (not M. Moe). There is no Index in the book though, so it makes finding things in the book difficult. A quick look didn't come up with anything. I'll take a closer look if you want...?

tyler1503 · Apr 18, 2017

Myka said:
Now that I'm actually physically looking for you so that I could quote it, I realize the book I have in mind is Conditioning, Spawning and Rearing of Fish with Emphasis on Marine Clownfish by Frank H. Hoff (not M. Moe). There is no Index in the book though, so it makes finding things in the book difficult. A quick look didn't come up with anything. I'll take a closer look if you want...?

Thanks for looking! Don't go to any trouble though. I'll keep an eye on my ammonia and cycle the tank as normal

If I don't see the ammonia spike I'm looking for, I know something's happening with the freshwater bacteria! Thanks.