Adding new substrate.

I changed from gravel to eco complete after my tank was up for a month and things went well. No fish died and my plants were O.K. I drained my tank and saved most of the water, carefully removed the gravel and put the substrate and water back in. I'm not sure about the fluorite but the eco only clouded my water for a few hours. I didn't go with fluorite because I read it's messy to work with. The eco complete doesn't cloud the water when you plant plants and clean the bottom etc. I've had it in there for about 8 months now and I am completely satisfied. When you have substrate instead of gravel you don't suck up the bottom with a gravel cleaner either. You just skim the bottom to suck the junk off it, it works well after you get the hang of it. I hope this bit of advice helps.

actually, i am planing to mix my old gravel and new substrate.
So you said once having a substrate, one dont need to do the gravel cleaner often. Is it because it will cause some loss of nutrient in water ?

You still need to do about a 20% or so water change weekly and the idea is not to suck your substrate up with the gravel vac, the plants get most of their nutrients through the roots rather than the water. It's allot lighter than gravel and will get sucked up with the waste water easier. Plus you don't want to disturb the root system of your plants once they get growing nicely. As for mixing the substrate with gravel I'm not sure. My LFS told me it's best not to so I didn't. My tank did cycle again but the beneficial bacteria in the eco made it allot less stressful on the fish, plus my filter was established too. I would wait and see if anyone with experience with fluorite can answer about mixing. I just followed the directions on the bag of eco complete and all went well.

sure u can. but there is one thing though. u have to wash ur flourite and u are probally going to have to break down ur tank.

by that, i mean u have to take out all the fishes and plants.

i have a method for my flourite, i put it in a large pan spread out and use a garden hose to wash it. put the spray nossle to get water flow underneth the gravel. adjust the pressure so that it doesn't go crazy and loose all ur flourite. do this for a minute. then repeat. afterward just dry it out and then put in int ur tank. then slowly fill it with water

i did that and my tank was clear in less than 4 hours. it was crystal clear the next day.

ok thank for the advice

Even using the substrate like eco or flourite, we still need to replace them after a certain of time, just like the root tab, right ?

I talked to a tech at eco a while back and asked the same thing because I wanted to know how long the investment was good for. He said it lasts indefinitely. There are some people in the forum who have had eco in their tanks for a few years with no problems. I'm pretty sure a supplement like Excel or Flourish wouldn't hurt and of course co2.