Water testing during cycing

[davidmold]

Hi, I'm doing a fish-in cycle to start my new 20 gallon tank. I have 6 neon tetras, which went in last week. I test the water each day. On day 2 and 3 there was a little ammonia (0.25 ppm) and I did a 15% water change on day 4. Since then, the ammonia is at zero, nitrites and nitrates have remained zero (this is day 8). There are no plants in the tank.

From what I had read, I was expecting more ammonia than this by this time. Any ideas why the readings aren't going up?

Also, all of the articles talk about any level of ammonia or nitrite above zero being dangerous for fish. This is no doubt true, but it seems that many people do successful fish-in cycles nevertheless. I can find no published information on how much ammonia or nitrite fish will tolerate. Unless one knows this, it would seem impossible to judge when to change the water during a fish-in cycle. Does anyone have any thoughts on this?

Incidentally, now I know that one can do fishless cycling, that would be my choice. However, I started this with information from the tank instructions and a book I bought, neither of which mentioned the possibility.

 

[YahooFishKeeper]

6 neons in a 20 gallon! LOL. thats hardly a bio load. if you monitor every other day it should be fine. i would stock very slowly though. LOL. people usually come on here and are like i have 2 clown knives, 4 pacus, 23 goldfish, and a couple of bala sharks in my ten gallon. you should be fine. is this a 20 long, tall, or regular? if its long you can stock slightly heavier, because of all the surface area, if its tall its the opposite.

 

[Lotus]

This is a nice article on fish-in cycling: http://www.aquamaniacs.net/forum/cms_view_article.php?aid=14

The levels of ammonia and nitrite that are fatal to fish depend somewhat on the type of fish. Anything over 1ppm means it's time for a water change. Keep testing every other day to make sure your levels are staying within normal. If you're showing zero nitrates, it's an indication that you're still cycling, and it's not time to add more fish yet.

 

[Iamcyy34]

Splendid article Lotus. Thank you for digging that up. I can assure, that will be very beneficial to future and present beginners.*thumbsups

 

[ZenGoalie]

I started my 30 gallon with 4 zebra danios and 1 rosey barb. I've gradually added a couple of fish each week. It's into the 3rd week now. The ammonia has dropped, and the nitrites have been spiking. Good news is that nitrates are also climbing up too. I've been doing water changes (5-10 gallons) each day or so. So far haven't lost any fish. Good luck! I'm wondering when the nitrite will drop...anyone have some ideas?

 

[davidmold]

6 neons in a 20 gallon! LOL. thats hardly a bio load. if you monitor every other day it should be fine. i would stock very slowly though. LOL. people usually come on here and are like i have 2 clown knives, 4 pacus, 23 goldfish, and a couple of bala sharks in my ten gallon. you should be fine. is this a 20 long, tall, or regular? if its long you can stock slightly heavier, because of all the surface area, if its tall its the opposite.

Thanks for the reply. The tank is 24 x 12 x 16 inches high - I imagine that's regular. All the articles I've read about fish-in cycling seem to stress the importance of starting with a small number of fish.

The levels of ammonia and nitrite that are fatal to fish depend somewhat on the type of fish. Anything over 1ppm means it's time for a water change. Keep testing every other day to make sure your levels are staying within normal. If you're showing zero nitrates, it's an indication that you're still cycling, and it's not time to add more fish yet.

Thanks for the link to the article. I note that it also doesn't give figures, so I'm grateful for your estimate. I guess my test results don't really fit with the schedule in the article, but perhaps I don't have enough fish to register much of a peak in either ammonia or nitrites. If that is the case, then I guess it will probably be quite some long time before I start detecting nitrates.

 

[Toddlee]

It took my 29Gal tank 60 days to cycle with 3 Danios. Hang in there, it will happen.

 

[Lotus]

For anyone who is interested, the pH and temperature affect the toxicity of ammonia. The higher the pH, the more toxic, the lower the temp, the more toxic. Ammonia can dissolve the mucous membranes (like gills) as well as skin and intestines, causing internal bleeding. Of course, this is why fish used for cycling can have a shorter lifespan.

With nitrites, it depends on the species. Delicate species can die at 0.5 ppm ammonia, hardy ones can tolerate up to 100ppm, the most common lethal level is between 10-20ppm. Nitrate basically breaks down the red blood cells, so it's suffocating your fish to death.

 

[davidmold]

Thank you Lotus, that is excellent and very useful information. May I ask how you learned about it? I would very much like to understand the whole subject better.

 

[Lotus]

I have a book on fish health that has explanations of the various water parameters and their physiological effects on fish.

 

[MortiferousSoul]

whats the name of that book if you dont mind sharing ? sounds like an intresting read.

 

[Lotus]

It's Manual of Fish Health by Dr. Chris Andrews, et al. It has lots of really good info on water chemistry, fish physiology and diseases.

 

[lou48314]

Not much of a bio-load with only six tetras.
I have learned that it is best to go slow. Take your time and stock the tank S-L-O-W-L-Y! You will enjoy it more if you have fewer problems.
Overstocking is a common problem.
You can overstock and be all right if you do water changes on a semi-weekly basis.