Have Gravel Want Eco Complete

[love cichlids]

I have a 30 gallon with tetras and femal bettas with 5 plants in it. I have already added co2 to tank, getting proper lighting next week so no limit on plants.
Now just have to figure out how to change from gravel to eco-complete. Should I just leave my gravel in and put eco-complete on top. I heard that eco-complete is very good but it gets compacted and some people have used some gravel on bottom, is this a good idea.
If only eco-complete in tank, how do I change it with fish in the tank, should I take them out.
Is this going to mess with my cycled tank. Been running for 5 yrs now with no crashes in my cycle.

Any advise on this would be appreciated.

 

[love cichlids]

need a reply before monday please

 

[Castellop123]

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[love cichlids]

ok I have my work cut out for me. I do have a large plastic bin that I can store alot of the water in and a pail to put the fish in. So on Monday or Tuesday I will go get the substrate and some more plants. Wow, that is going to be fun to bring home, across city, on the bus . Yes, I need to go get my lighting that day also.
I just remembered my neighbor has one of those wire push cart that people use for grocery shopping, maybe I can borrow that. She is really nice, there should be no problem. Whooo, that will help alot, thankfully I remembered she has one.