concerned on cycle

my tank is about 2-3 months old, i left it running untouched for the first month with live sand only, then added some live rock, checked the water before every water change during that month as well all read like should be, then come about second month all droped way low, not zero just low nitrite at .50 ammonia at .25 and nitrate at 20ppm never had a major diatom outbreak, just the live sand look like something had taken a dump over it. the main place the diatom was in my fuge where i had my chaeto (put it in the second month) it was all over the top of the sand in there., now i have a few damsels in my tank (i was told they are the heartiest fish for the cycle) when i put fish in i added a carbon filter been about the last month since i put first 4 in now im up to 9 damsels in there and all the reading are setting right at .50 ammonia at .25 and nitrate at 20ppm. is the cycle not complete or did the chaeto help keep the bloom down while it was going or did the chaeto screw my cycle up when i saw the little bit of bloom i did another water change and vacumed the sand to remove it was i not supposed to do that just a little concerned :-/

 

If you had no fish you really didn't need to do a water changes unless your nitRATE was quite high (end of the cycle) and ammonia and nitrite were 0...
Idealy:
Your ammonia should be zero.
Your nitrite should be zero.
Your nitrate, well low as possible but I'd say less then 20 ppm for juvenile fish should be safe for now whilst your tank matures.

It sounds like you MAY have never really had a good cycle from the start if you have ammonia present.

Since you have fish now and there is nitrite and ammonia present, I say the safest thing to do would be do go get yourself a bottle of Bio-Spira or some type of instant tank cycle in a bottle. That should save the fish and you will prob be fine from then on out with regular water changes.

What size tank, we need more details. Equipment list?

 

55g main display 40g sump pvc skimmer usin 2 limewood stone found the plans online seems to work pulling some gunk out, but ill use the bio spira

 

Are you using an API test kit? Was it a new kit and not expired?

It can be very tough reading the ammonia with the API. Often times it looks like 0.25 when it is really 0. How much live rock did you add?

For reference, I also recently started up a 55 w/ 30 gal sump, with regular sand and 40-50 lbs live rock (along with 50 lbs dry rock). I did not use anything at all besides the live rock to cycle. Ammonia was around 1 for the first week, then went down to 0.25 or 0 (again hard to tell!) and nitrites up to 5. A couple days later nitrates were up to 20. After 16 days ammonia and nitrites were 0, nitrates 5. One more week and all were 0. I did not do any water changes during the cycle. Snails and chaeto were added about 1 month into the cycle (when all tested 0).

How fast did you add the damsels, and how big are they? Adding too many at one time can cause a mini cycle as you are greatly increasing the load.

 

Yes its the api test never thought about the ammnioa being hard to read but thinking on it your right it is hard to read but the trites should be 0 as for exp date idk its maybe a year and a half old 2 at most nevetr thought it went bad that fast
Added 2 at a time every week 4 in the first week. All are 1-2 in long

Just checked all my test are still good, I found the lot date all were made in early 2011 so they are all just over a year old