Strange Growth on Rock

**ericp2311** · 05-02-2012, 04:49 PM

Greetings,

Quick question: I am in the process of cycling a 29 gallon using the fishless method. Current water parameters are:
Ammonia 1 ppm, level maintained by adding ammonia every morning
Nitrites 5ppm, reading as the maximum on the color chart, so it could be higher
Nitrates approx 20 ppm

I'm a little surprised to be reading nitrates so early on in the process (less than two weeks). I thought it would take a while longer for them to show up.

My question is that I've noticed a fuzzy, white moldy growth on one of the large rocks. I have attached pics.

I wonder if I should take the rock out and scrub it off with a coarse brush and let it sit in a separate bucket for a while, or perhaps boil it on the stove. Or maybe just leave it alone? What do you all think?

**Cermet** · 05-02-2012, 04:59 PM

First off, your nitrites are too high and will interfere with the cycling - do a large water change to get the nitrites below 1 ppm. Your dosing of ammonia is excellent. Your nitrates are high, but the WC for the nitrites will fix that too.

The growths look a little like fungus but I'm no expert - others may have more information. If it is a fungus, I'm at a lost to know what it could possibly feed on.

**ericp2311** · 05-02-2012, 05:22 PM

Alrighty - one large water change coming up as soon as I get home from work this evening. I assume that since the tank is still cycling, I should avoid stirring up the gravel? Is 50% too much water to change?

**Cliff** · 05-02-2012, 05:29 PM

I wish I could help identify what that stuff is growing on your rock. Just to safe, I would suggest just cleaning that stuff off. Better safe than sorry

I would also wait a few days before doing any waterchanges. The nitrite eating bacteria grows a lot slower than the bacteria that eats your ammonia so they will need time to catch up. If you don't see the nitrite levels changing after about 5 days, then I would suggest about a 50% waterchange.

As you already have a good level of nitrates, I'm guessing the nitrite eating bacteria is off to a good start and just needs a little more time.

**escamosa** · 05-02-2012, 08:34 PM

I agree with Cliff. If you're doing a fishless cycle, then there really is no need to be doing any water changes at all. In my opinion, those perameters look great to set up a very nicely cycled tank. I would leave it alone and let it run its course.

**Cermet** · 05-02-2012, 08:53 PM

I now agree with Cliff - the water change should wait. Lowering the nitrites that low would interfere with the nitrite growth. I was thinking ammonia levels ... .

**ericp2311** · 05-02-2012, 08:56 PM

OK - water change, cancelled!

But what about the fuzzy white stuff? Leave it, or attempt to remove it? I could swing by the hardware store on the way home and grab a coarse metal brush.

**Cermet** · 05-02-2012, 09:07 PM

Good idea to clean it off but isn't a wire brush rather aggressive? Could a regular scrub brush work with hot water? Maybe even boil the rock first, and after it cools brush away any leftovers?

**Honey Badger 1** · 05-02-2012, 09:32 PM

Boiling rocks is not a great idea, some will explode. Personally I would just leave everything alone and not clean anything during cycling. Just let it go until the cycle is complete then scrub it off in tap water.