High readings

Question
I have a 30 gal tank, its been set up for about 2 months I have been fighting these high reading ever since( pH 7.4 & ammonia 4-5PPM).  They would drop here and there and then spike back up.  I have done severeal water changes with spring water because of the pH in out tap water.  I have not over feed the fish and they seem to be doing well, I just don't understand the readings and why.  I have 3 other tanks in the house for years, this one is kicking my butt.  I have 2 Gouramis, 2 silver dollar and a pleco in this one.  I did not buy fish tank gravel, I used small landscape gravel from Home Depot, rinsed very well (I did this with my 155 gal tank years ago and never had a problem) would that be my problem this time?  I am exhusted from this tank.  I have used ammonia rocks in the filter and seachem neutral regulator. I have a ghost knife that is about a year old I need to move into there but I am scared to do it with these readings.  Any suggestions, please help?

Thanks  

Answer
With ammonia readings like you have your knife fish would not survive long at all. Have you ever tested your tap water seperately from your tank just to see what kind of reading you get?? Water changes are the best solutions for high ammoinia levels. I would not think the gravel you purchased would be the cause as you rinsed it well and it was not used for anything else but your aquarium. You may want to try a little trick I have used when I had a tank that the ammoinia was just crazy on, get an unworn nylong cut off the toe section, enough you can put some ammochips in it and rubberband it closed and place that in your back filter. Give a couple of days and retest your water. How large were your water changes? Were they large enough to cause your water to start to recycle? Let me know how things work out, I will also give this some more thought and get back to you if I come up with other suggestions. Best of luck.