There shouldn't really be one. Plants will take care of nitrogen cycle.AV8TOR said:
Planted Tanks and the "Silent Cycle"
Ammonia and Nitrite kits are usually useful when cycling a tank. However, if your tank is heavily planted, the chances are you won't see an ammonia or nitrite spike if you track these parameters when cycling. In fact, the only indication that your tank has cycled may be the appearance of nitrates. Even then you may not get a reading: heavily planted tanks with a light to moderate fish load often test zero nitrates, since the plants take up some of the ammonia before the bacteria convert it, plus most plant species can back-convert both nitrite and nitrate to ammonia (ammonium). If you let a large plant load get established for a week or two in your new setup, it's usually safe start to add groups of fish in weekly increments, but testing for zero ammonia and nitrite first is always a good idea. Remember to put in some fish food while your plant are getting established so they and the beneficial bacteria have some nitrogenous waste for food. In addition to planting heavily, it's wise to start out with a nice percentage of stem plants, which, growing fast, consume more nutrients (fish waste). Once your tank is well-established and in balance, you can start to replace some of the stem plants with slower-growing, rooted ones (if you like).