Nitrite Spike

[jtipton]

My brackish tank has been cycling with a single fish and some inverts for a little more than a week now. The ammonia dropped a few days ago, and the nitrites weren't too bad. Just yesterday, the nitrites went off the charts at about 10 ppm. My KH also dropped from around 200 ppm to 100 ppm, and the pH from 8 to 7.5. What the heck is happening? I added coral to my filter to try and raise the hardness. My fish is opening his mouth to move more water through his gills. I added AmQuel+ to my tank in an attempt to neutralize the nitrites while the bacteria work on them. I don't understand the strange water chemistry though. Should I move the fish to my quarantine tank?

Thanks for any help. I don't want to lose the little guy. He is very cool.

 

[jtipton]

I realized I hadn't added an essential detail. The tank has actually been cycling for 2 weeks. My crab has been in there from the beginning, the fish was added after the first week. I am now starting Week 3. So:

Week 1: Added crab and feeder shrimp
Week 2: Added fish and 5 very small hermits for algae control
Week 3: Added live tubifex worms for fish

 

[WILDER]

The nitrite reading does go off the chart when cycling a tank, it drops slowly then to 0.
Sounds like you havent long to go.
If any fish are looking stressed you have to do water changes and increase aeration in the tank.

 

[jtipton]

Thanks for the help. I will continue with the water changes, and try adding a bubble wall or powerhead to increase the aeration. I think that cycling accounts for the nitrite spike, but what about the pH and KH drop? I am using a calcite based substrate that should have plenty of buffering capacity. Here is a link to the substrate I am using:

Gray Coast - Calcite

Other than the sand, I have lava rocks, drift wood (old), and live plants. Plus, I added coral to my filter. My tap water is also naturally hard since I live in the Rocky Mountain region. My KH should be extremely high. Any ideas?

 

[WILDER]

Ask in general discussion about the ph and kh, science is not my thing.
This might help.
http/www.drhelm.com/aquarium/chemistry.html

 

[jtipton]

The link was perfect. According to the article, the pH is dropping due to the nitric acid building up. Aerating the water will drive off the carbon dioxide in my water, raising the pH, and kH. Still not positive about the KH, but may try some baking soda if it doesn't start rising after the cycle is complete. Thank again for your help.

 

[WILDER]

Alot of science buffs go to tropical discussion try there on your ph and kh.