Doing a big tank change in the coming weeks and had a couple questions. I've been running my 75 gallon low tech java fern tank for about 4 years now. Moderately stocked with nothing super unique or sensitive.
Play sand substrate
Eheim 2026 and 2217 canisters running
Haven't tested the water in a while. Tank is pretty old and mature. Haven't had any nuisance algae or major shifts in years. Tap water ph 8.2 usually

Tank looks like crap. Might be too large of water changes have created too Clean of water to grow anything. Lights are likely too low as well. I KNOW this is fairly vague but here's my point.

Mineralized topsoil is almost done, still deciding on a cap. Either will go with new turface/safeTsorb, or used Ada Amazonia. And when I remove all the sand and put in the new substrate I will likely plant pretty heavily right from the start with lots of stems and swords.

I was planning on putting my fish in a rubbermade storage tote and running one of the two canisters on it, the other canister being run on the tank. Still using tap water. How long should I drag out the re-acclimation? It's just a bunch of endler hybrids, some tiger barbs, and a big featherfin catfish. Nothing too delicate.

I was going to do a 1gallon water change a day. Basically removing a gallon from the display, and putting that in the plastic holding tank. A week be sufficient? Not intentionally trying to kill anything here but I'm sure the wife wouldn't appreciate a plastic tote on the floor for a long period of time lol. Does my plan sound solid?