Test strips are better than nothing but you really need to test for ammonia & nitrite with a liquid test kit. Maybe you can just buy the nitrite & ammonia test kits? You can order them really cheap online too, $20-25 including shipping:
http/www.amazon.com/gp/offer-listing/B000255NCI/ref=sr_1_1_olp?ie=UTF8&qid=1347496710&sr=8-1&keywords=api+master+freshwater+test+kit&condition=new
http/www.amazon.com/gp/offer-listing/B000255NCI/ref=sr_1_1_olp?ie=UTF8&qid=1347496710&sr=8-1&keywords=api+master+freshwater+test+kit&condition=new