If you give the gravel vac a rest around the base of plants and just suck up the surface dirt that you can get at easily, the plants will take care of using the nutrients from the detritus that falls into the substrate. One of the less popular but viable options for a heavily planted tank is called a Naturally Planted Tank, NPT. Diana Walstad is one of the promoters of the method, she suggests using the fish food to feed your fish and ultimately your plants. The idea is that you don't need any of the fancy fertilizers if you add in enough fish food that can decay into plant food and no added CO2 or other artificial ferts are needed. She does recommend that you start with a dirt or planting soil substrate with a final gravel cover to keep from having the dirt floating around in the water column. She does expect rather high lighting to be used even without the ferts and CO2 that the high tech people use. 50% weekly water changes are a very important component of what is known as the EI method, because the method relies on grossly overfeeding plants and then resetting the tank chemistry once a week by doing that huge water change, before adding in way too many chemicals again. The EI method has tons of adherents that hang out in our planted tanks area if you want to go that way. The Walstad approach, and it is one that I use, advocates a 50% water change about every 6 months to replenish the trace elements that come from tap water and that the plants need for good growth. This is a picture of my longest running NPT and as you can see it has significant plant growth in it. It is a 40 gallon breeder that has a 104 watt CF fixture over it, yep 2.5 wpg, and has had no artificial ferts or CO2 added for over 2 years. It gets a water change every 6 months or so whether it needs it or not. Algae in that tank is non-existent.
it is a nightmare with lots of heavy foliage in the way to get fish out. 
