08-22-2011, 10:41 AM
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I will expand a bit on the plant/cycling issue.
Plants assimilate ammonia/ammonium, it is their preferred source of nitrogen. One frequently reads that plants need nitrate but this is inaccurate; given the choice most aquatic plants prefer ammonium and will only take up nitrate if ammonium is exhausted. Ammonium comes from the water, assimilated through leaves and roots. The faster growing the plant, the more ammonium it uses.
Fish and bacterial processes produce ammonia which will be changed into ammonium in acidic water and used by the plants, or in basic the plants have the ability to take up the ammonia and change it to ammonium. If forced to use nitrates, they actually take these up and change them back into ammonium before they assimilate the nitrogen as nutrient.
In a well planted tank, the nitrifying bacteria will be much slower to colonize and will be in far fewer numbers than in a non-planted tank, all else being equal. This is because the plants grab the ammonia/ammonium much faster than nitrosomonas bacteria. And with fewer nitrosomonas bacteria using ammonia and producing nitrite, there is far less nitrite, and thus less nitrate. This is why nitrates in a planted tank are often minimal, zero or 5-10ppm depending upon the fish load. The plants assimilate a vast amount of ammonia/ammonium.
So yes, there is a "cycle" still, but it is so minimal you cannot detect it with our test kits. Ammonia and nitrite will read zero in new tanks if there are sufficient plants for the fish load from day one. I have set up dozens of new tanks with live plants and never experienced any detectable "cycle" because of the above. Diana Walstad writes about it in her book, as do many other planted tank aquarists.
You also do not want to encourage biological bacteria in a planted aquarium because this competes with the plants.
No one has yet found a safer method of setting of a new tank than with live plants; and I agree, faster growing such as stem and floating are advisable. But I have done this with a tank of swords (Echinodorus) and floating plants very successfully. With sufficient plants, you add fish the first day and there will be no problems. But until one is experienced, it is best to start with very few fish.
With respect to disinfecting plants, Rhonda Wilson (monthly columnist in TFH) says anything strong enough to kill all bacteria/pathogens/snails on plants will harm the plants and may kill some. She recommends not bothering with treatments. In my 20+ years I never have.