RS, wondering how you're going to filter all those aquariums?
Since they won't be display tanks for the most part, I'll just use sponge filters (I like Azoo sponge filters)... which are cheap ($5 to $10 apiece) provide a place for beneficial bacteria - which handle the ammonia cycle - to grow.
Some of the beneficial bacteria consume ammonia - a highly toxic fish waste/decay product - and convert it to nitrite, which is still pretty toxic, but much less so than ammonia.
Still other beneficial bacteria consume the nitrite and convert it to nitrate ... which is way less toxic than the other two.
The nitrate gets handled either by doing partial water changes, or by setting up a specialized filter whose design and media allow anaerobic bacteria to grow. Anaerobic bacteria will actually consume the nitrate. Plants in the tank will also help, as they consume nitrate as well ... since it's a fertilizer.
Part of the reason for moving things into a single room and setting up racks is to make it easier to properly maintain the tanks. All the racks will have drain pipes (1" to 2") mounted on them that are plumbed into a sanitary drain that runs to our septic ... so that I can do water changes without having to lug buckets of drained water. If I get real frisky, I might eventually drill the tanks, install bulkhead fittings, and hard plumb each tank into the drain lines at some point. Then it's just a matter of opening the valve on a tank to drain it.
The replenishment water supply will be fed from hose bib that has a Honeywell water tempering valve plumbed into it, which will mix hot and cold water to within a few degrees of whatever temperature it's set to.
And what you do for de-chlorination?
We're on a well ... so no really chlorine to deal with ... other than when I use chlorine bleach to clean/disinfect something.
In those cases, I use a product called De Chlor (in a little green bottle) ... just takes a few drops to neutralize chlorine or chloramine.
Do you use a UV bulb in the flow to kill algae?
Nope ... algae is either fish food itself, or a place where fish food (aufuchs*) grows and lives. Most of the fish I keep graze on and pick at it continually.
(Aufwuchs (German "surface growth" or "overgrowth") is the collection of small animals and plants that adhere to open surfaces in aquatic environments, such as parts of rooted plants.)
Many (probably most) of the fish I'll likely raise (African Rift Lake cichlids) are omnivores ... and for many, their primary diet in the wild is the aufuchs. Their digestive tracts/intestines have evolved over time to be quite long, to aid in digesting the high amount of plant material that they eat. Feeding them a diet with too much animal protein will actually cause an often deadly disease - called Malawi Bloat - as their gut/intestines pack up and clog.
So (for non-display tanks) I just let algae grow for the most part ... until it gets to the point it's hard to see into the tank through the front glass, then I'll clean it off with a Mag Float ... so I can keep an eye on things. I have two tanks that are currently in that state, where it's actually getting tough to see into the tank through the front glass due to all the algae. The fish don't seem to mind however.
Will you connect them? Or keep them isolated?
Isolated for the most part, although the 100G Long will be a display tank and will have a 55G tank below it in the cabinet as a sump filter that it's plumbed into.
I hate to see dead fish at the pet store and see the water flowing from one aquarium to the next.
The only kind of dead fish I like to see is one I'm going to eat.
My daughter can't understand why I tell her to turn down her music on her cellphone...Hearing music from a 5mm x 15mm speaker just leaves something to be desired.
LOL ... no doubt.
Probably partially explains why I keep getting rebuffed, every time I suggest to the wife that she could watch a movie on Netflix on her cellphone.