I would like to add some eco complete to my 75g to help with my plants and I like the look of it. My question is how many bags would I need? Here is a picture of my tank. Thank you!!
I mixed black flourite and eco-complete (flourite on the bottom, eco on top) and I think I used 2.5-3 bags of eco-complete and 2 bags of flourite for my 75 gallon to get ~2-3 inches of substrate.
I didn't realy want to start over as I don't want to take the chance to loose the fish I have with another cycle starting. I was going to try and mix the Eco complete with the gravel I already have, but I guess if I have to start over it will be worth it in the end.
As long as your filter media stays established, you won't have to start completely over. you may run into a slight spike, but nothing you can't keep in check with more thorough testing and a couple extra water changes.
I have never used Eco-C, but I just changed my 55g over from gravel to ColorQuartz (sand) a couple of weeks ago. I turned the filters off, drained about 50% of my water, and scooped out the gravel. I then added the ColorQuartz using a plastic cup to keep it from stirring up in the water. Once I had it like I wanted, I added my rocks and driftwood back, filled the tank back up, and let it sit for about 30 minutes to settle any floating sand. I did see a slight nitrite spike but after a water change and a couple of days my tank was stable again.