Ammonia/Nitrate levels and fish.

Hey so I picked up some API test kits today. My 20gallon high is probably been setup for 5 weeks now. I just tested for Ammonia and on the color card it ranges from 0ppm to 8ppm. My corresponding color is most likely .25ppm or less. The nitrate color card ranges from 0ppm to 160ppm. My corresponding color was about maybe 1.5ppm (max) looks less than this but I just want to be safe. Im assuming based off these values I am ok to add my cleanup crew, but what about a fish? I have a chromis that has been in my tank for a few weeks that seems to be doing fine ( I know i never should have added him, LFS said it was ok.......now i know better) But what do you think about my values and their affect on livestock? Thanks for all the help 3reef, glad i joined.

 

You don't seem to be done with your cycle if you see any ammonia. Do you have any Nitrite readings? If anything you're cycle is very weak and if you're going to add anything, I would only add a small clean up crew. Then wait a another week or 2 and add a fish if you see 0ammonia, 0Nitrite.

Also do you have any Live rock? Did you try anything to kick start the cycle? (frozen prawn, bio-spira, ect..)

 

I have about 16# of base rock with 4# live rock seeding it along with 15# roughly of live sand. Why would my cycle be very weak? Shouldnt i be almost at the end, if not at the end of my cycle. To be honest, I bought a chromis which i kick started the cycle with along with the addition of some food. The large amount of diatom growth shows that my tank has been significantly cycling but I am pretty sure that this will soon turn to algae considering it has grown less recently.

 

Well its weak because you don't have a very large biological load so adding any relatively large fish or many small ones could tip the scales and allow the ammonia and nitrites to rise. Secondly, if you are detecting any ammonia with an API test, that is typically a sign that your biological load is currently larger than the bacteria in your tank supporting it. I use those test tube tests a decent amount especially for ammonia and I have never seen it turn a different shade of green than 0ppm for a tank I considered cycled. Also the diatoms while can be an indicator for your cycle, it isn't a perfect one nor as reliable as reading your ammonia, nitrite, and nitrate levels.

Also what is your nitrite levels?

I know the feeling, it can be difficult to be patient with this stuff. Waiting can't hurt while perhaps adding more fish could cause problems. I don't think you have the intention to hurt the fish one bit and not saying it will for certain, just more likely than if waiting. What fish are you looking to put in there, because that makes a big difference too. Clearly a damsel and probably even a clown fish could live in those conditions.

 

I only picked up 3 blue leg hermits tonight and no fish. They seem to be doing fine in the tank so far. The fish I would like to have in this tank eventually would be possibly any of the following:

-bicolor blenny
-hi fin banded goby (would love to have the pistol shrimp combo)
-emerald crab
-skunk cleaner shrimp
-maybe an occellaris clown? (lastly cause i heard they are territorial if introduced first)

Havent picked up a nitrite test kit yet, will do that soon and ill test.