Pyewackette

I just did this myself a few days ago - forgot and put some still moist clay to slake in a bucket.  What I SHOULD have done was let it dry out completely, THEN slake it.  Or in your case I would suggest cutting it into thinnish slabs, letting it dry, breaking it up a bit if necessary and then putting it in with your other dry clay (trimmings I guess)?
Dry clay scraps slake a lot faster and more thoroughly than wet.  I knew this but forgot anyway LOL!
I don't know about the algae, I'll let others comment on that.  Potters typically don't care much about moldy smelling clay but algae?  Not sure.
I'm not sure why you have 3 things going with "greenware" which I assume means pieces you've let dry but don't intend to fire; trimmings which I think must be the scrap clay when you trim a piece; and then slops which I think you are calling "waste".  IF that is the case it is fine to let all three mingle, as it were.  But in a dry state, and slake only when you are ready to reuse.  Then you slake it, put it to dewater on a 3" thick slab made of (NOT PLASTER OF PARIS BUT) #1 Potter's Plaster, hydrostone, or hydrocal - hydrostone is my favorite - or a sheet of 1/2" (really .42") hardiebacker.  NOT DUROCK OR ANY OTHER BRAND OF TILE BACKER BOARD.  It comes in 3x5 sheets, you would need to score and snap it to about 2x3 or whatever size you feel is appropriate for a dewatering "board".  You could try layering 2 pieces that size and see how it works - the draw back of hardie backer over plaster for this purpose is it is so much thinner than plaster, but that is also its advantage.  You can't schlep a 3" thick slab of plaster around very well, but you can just lean the hardiebacker up in a corner or behind something when not in use, or carry it off somewhere for storage. But because it is so much thinner you will need to lay the wet clay out on it in strips to dry.  Otherwise if you put down one mass of clay it won't dry in the middle as fast as the edges.
I've used it this way but I just had the one piece - when I set up my studio I'll try double or triple layers and see if that works better to dewater.  It works great as ware boards or drying boards.  I think if it were thicker it would work better (as it is it works way better than plaster of equal thickness) if it were thicker, but I don't know if it would get good enough contact between pieces to help when dewatering.  Two .42" thick pieces is not the same as one .84" thick piece, if you get my drift.
Consider renting a small storage space until you can get a studio.  Some of them have electrical outlets and some are even "climate controlled". Even if not suitable to work in (and I know people who have used them as studio space for a variety of activities) you could at least free up some room on the boat.  You would most likely have to schlep water there if you tried to work in there, guerilla style.

violette,  is the studio you find uncomfortable one where people keep their pieces wet for a long time?   is the throwing water kept for days?  are there barrels of water for reclaiming studio clay?   is the humidity level high all the time?
in your own studio you can be a rebel.   work as dry as possible, keeping the place clean and dry.   there is no reason a modern studio should resemble something from the middle ages.  i remember walking into one in brooklyn.   the floor was covered with 4 inches of clay dust.   i left in a few minutes, sure i would have an asthma attack if i did not leave. 

In my experience, very few people are affected by the molds in clay. I've spent 8 years in University studios, 3 years in a clay supplier business, and 17 years teaching classes in my own studio, and I've only run into two people that had to drop classes due to mold sensitivity. I've got students with immune deficiency conditions (I don't know the specific conditions) and it doesn't affect them. Mold is unavoidable in the clay itself, short of mixing your own clay every time you go to work with it, which would be very poor clay to work with. And doesn't seem to be the type of mold that causes strong reactions and health issues like you'd get in moldy drywall. If it was we'd all be experiencing health issues every time we opened a bag. I think that testing a bag of clay for specific molds would be useless because the clay body materials are sourced form different places and you would/could get different spores from every batch of raw materials.
The studio itself is a different story. There's no reason it should be any more moldy than any other environment due to the clay itself. If your local studio is musty, I'd first determine if the issue is the clay, or something else like a damp basement, etc. Just using clay in a space shouldn't contribute to the mustiness if the space is dry in the first place, because the mold needs moisture to proliferate. If the smell is from slop buckets or standing water in the sink, those issue can be easily dealt with. However I've got open slop buckets in my studio, and we do not have any oder or mustiness problems from them. If we did, then lids would solve the problem there. 
Personally, I'm allergic to molds in the environment, and my allergies are always a mess in the Spring when it's rainy and in the Fall from leaf molds. The studio environment never sets them off, though.

Some days, there ain't much view at all! 

Here is the view from my Summer Studio (on the back porch).

Yes that's a pile of brush.  I cut down a Holly tree that was crowding the eaves awhile back because (a) it had been hacked into pompom shapes at some point and (b) it was too big for where it was at even if it HADN'T been turned into a monstrosity of psudeo-topiary.  I'm working on it.  I am building a beetle bank as I cut it up into smaller pieces.  I'm only recently beginning to be normal, health-wise, again.
And those are my curry leaf plants - what's left of them after 6 months of torture - in that cage to protect them from the blue jay that has developed a taste, apparently, for Indian herbs.  @Hulk my orchids got left behind in the move.  I'd had them for 3 years.  Poo!

(I had been painting, that seemed like the never-ending-renovation)
They bloomed every single year.  I can't believe that's the only picture I ever took of them.  I miss my orchids!
Still haven't found my bats.  I was hoping there was at least one in the box with the wheel, but NOOoooOOooOoo!  I'll have to borry one from the studio until I find mine or get some, or I break down and make the hardiebacker bats I've been threatening to make.  They're cut.  I just need to measure for the bat pins, find some tubing as hole protectors, and Do It.
And here is what I have to look forward to when it gets cold again:

Minus the washing machine and accoutrements which are going next to the kitchen sink.  It's a little Magic Chef portable washer, the middle sized one.  The whole room is all of 6'x6.25'.  No windows.  Barely any space at all.  There is a utility tub on the wall to the left in the garage so there is that.
So yay!  Guess which space I prefer!

As an example here is the entry on cracks http://ceramicsfieldguide.org/pdf/materials-handouts/ClayCracks.pdf

Shelf protectors like that are sometimes called wasters because they’re not expected to survive.  If you’re making them out of a stoneware you know to be more refractory than the earthenware you’re testing, shrinkage isn’t going to be a big issue. But consult with the head tech person at your studio to see how they want you to work that. It’s their equipment, and they may have preferences. 
If you liked Tony’s articles on glaze and clay experiments, you’re gonna love the materials listings he’s got. Here’s the link for talc, and the why’s and wherefore’s of its use in ceramics. https://digitalfire.com/material/talc . It’s usually added to low and mid fire clay bodies to help with thermal expansion/glaze fit, but there’s other stuff too.
Digitalfire is a godsend to us all, as is the Glazy calculator. You’d also like the Potter’s Dictionary by Hamer and Hamer. Although that book is a bit of a spend, it’s worth every penny.

"Studio" the last few weeks.
Here we're building out the cinder block 2.75", filling the bays with 2" insulation foam, pulling new wiring all around, hanging and finishing sheetrock, repairing and restoring the ceiling and other walls, texture, prime, paint, electrical finish.
Next, the third bedroom, which has one exterior wall, one window.
Here the lid is painted, next, walls.

Next door.
Toms are full on this time of year.

Part of the reason Hansen works the price out at $150- CA a box is the porcelain he gets that figure for uses Halloysite (expensive), 30% frit (expensive), VeeGumT (expensive). If what he says holds true for an earthenware version of that clay needing only 5% frit then adding that amount of Ferro 3110 would add about $10-20 to 100 lbs of your dried free scrap earthenware (if it works). If the earthenware needs more plasticity (throws better) then 1-3 % bentonite (inexpensive) could be added, no need to use VeeGumT in earthenware. If my studio wasn't packed up I would mail you a bit of 3110 to try this out. Would the studio you go to sell you a little if they have it?
Some earthenware can be fired high enough to produce a fairly tight body without bloating, it's the old test it and see what happens. (using a drip saucer under test pieces).
BTW Boxes of Plainsman clay are 44 lbs.  Hansen doesn't own Plainsman Clay.

Historical  aside Code stone. Sold as an artificial stone, it was really a ceramic with a very narrow firing range.

Coade stone https://en.wikipedia.org/wiki/Coade_stone
The Secret of Coade Stone https://tinyurl.com/y2ckdhyy
What is Coade stone? https://tinyurl.com/2s3b5j76

@Hulk My first car (that ran) was a 69 VW Fastback.  I loved that car!  She had a name.  Lola.
I was almost all set to rebuild her engine (I was just waiting to catch the Snapon Tool Man for the last tool needed) when I opened the trunk one day (in the front of that car) and I was looking at the tire, and it wasn't the spare.  Turned out the only thing holding it together was the heavy duty trunk liner.
Lola:  RIP.  Died of terminal rust.

@Hulk My first car (that ran) was a 69 VW Fastback.  I loved that car!  She had a name.  Lola.
I was almost all set to rebuild her engine (I was just waiting to catch the Snapon Tool Man for the last tool needed) when I opened the trunk one day (in the front of that car) and I was looking at the tire, and it wasn't the spare.  Turned out the only thing holding it together was the heavy duty trunk liner.
Lola:  RIP.  Died of terminal rust.

I have alot of brushless cordless tools now-the drill and impact drivers are great-lots of power.

Reading up on direct current motors, seems that brushless are better in just about every way, except initial costs.
Expect more brushless motor pottery wheels down the road, maybe.

Blame variable speed drills where we decided it’s better to raise the voltage up a bunch then chop it into three phases so we can make it variable speed. No one wants to go back to brushed motors and low battery life anytime soon. The downside, it’s easy to make torque using a drive belt and a small and large pulley. The upside, no belt maintenance,  very precise control and maintenance of speed under load or unloaded and …….. no noise. Electrical slip is quiet but unfortunately hard to get torque multiplication without that belt radius thing. Nice wheel, has its pluses and minuses. I do like the quiet operation but definitely takes getting used to for some.

I prefer waffles, then egg soaked fried in butter bread, aka "french toast" - but pancakes are solid third for me in traditional just in time breakfast stovetop fare - without gettin' into special, e.g. croissant, raised biscuit, xmas morning bread...
In motor talk, "pancake" typically refers to a flat/horizontal space saving design, like what VW put in the fastback type cars, and the later model buses. It's flat.
The Whisper doesn't use a belt and pulley - it's direct drive, and the motor is brushless. It also looks kinda flat.
Looks like replacements are somewhat expensive.
 

I LOVE how quiet they are.  I can hear myself think!
Are you sure you're not thinking of the VL Lite?  That's the one I have at home.  I've thrown more than 10 lbs (in the past, not back to that yet) on the Whisper and it was fine.  The VL Lite will only handle 12 or 15 lbs ...
What's a "pancake motor"?

Crispy tofu marinated in dark soy sauce with lots of ginger and chili oil with sweet and sour veggies on basmati rice. Bowl is one of my dinner bowls (that we use more than dinner plates).

Harbor Freight has some big blue plastic tarps  that are inexpensive,  sometimes they have a sidewalk sale and give them away.   Put your wheel on one and hang a  couple on the wall,  clean up everyday so you don't track clay around.   Throw a little drier by just wetting your hands not the clay,  keep a small wet sponge in your hand to squeeze some water on the clay.    I had a professor teach my class to throw this way.    When I trim clay that is starting to get too dry I have a bigger mess.   Winter is many months away,  you have plenty of time to plan your throwing inside.      Denice

I think you were on the Europe site.  The US site still has all the names you're used to. There's a little flag icon in the top right corner to toggle between the sites.
Watts don't matter, HP doesn't matter. Torque is what matters, however nobody lists actual torque numbers. The closest we get to torque numbers is centering capacity. Can a tabletop wheel center 22 pounds? Probably not very well. Can a regular wheel center 200 pounds? Probably not very well. But they can all center 25% of that just fine. Brent switched to listing what the clay can handle 'continuously' rather than centering capacity, so that further complicates things. I think they only want you to compare their wheels to their other wheels, not to other brands. But who cares if a wheel can spin 225 pounds? Nobody does that. It's all about torque. I wish there was a standardized, real number system for rating wheels. Even centering capacity is subjective.

Hello Pres,
As I was trimming a pot last week, I started wondering if others trim pots just to clean them up and establish a foot, or is trimming part of the creative process for you?  I like when I have extra clay (thicker walls & bottom) and can change the intended look of the pot depending on my mood that day. 
Betty
 

thanks, hulk.   i think the beginners who have visited my studio overlook the things that are important to me and just think i am mean or wacky.   i am probably viewed as  overly fussy about keeping the work under my hand clean by avoiding the tiny bits of clay that have separated from the actual piece being worked on.    if you have ever picked up a piece of handwork that has a dozen tiny bits stuck to the bottom, you see what i mean.   there are 2 small boxes attached to the table holding my slab roller so i can brush those bits into the box nearest my hand.   they sit there for months out of the way and not getting turned into dust on the floor.
those tiny stuck on bits make me unhappy, they call attention to the lack of care that i think we owe ourselves, not just for whoever picks up that piece in future.
and tools need to have a place to be when not in my hand.  not scattered all over the room just because i moved the piece or walked to another spot to pick up another tool.  so i provide a space for tools.   unfortunately, i keep adding more tools and the really generous space i started with now resembles a dump.   but exactly where i work is clean and it stays clean and i leave the space clean when the session is over so the next time the space is welcoming.
(funny, i can't seem to work that way in the kitchen)
 

Absolutely, the pots definitely work, very nice.
As for qow, there are some pots I don't trim, but not many.
I like
a) to establish the ring where the finger catches on the bottom, particularly for unhandled ware, so there's a closed angle between thumb and fingers (I have "bad" thumbs)
b) to trim the portion within the ring to match the contour of the pot, which typically has a slight arc to it, which then flattens a bit in drying
c) to glaze the portion within the ring
d) to burnish the clay, particularly the bare part
e) to tool the portion within the footring
f) chatter mark
Hence, both, it's clean-up, for there's clay to remove, and enhance, per I like, above, however, trimming is just part of my process, and the ring is mainly practical for me.
As for being part of the creative process, yes, I believe so. The humble portion - it's part of the pot, after all! 
Here's the mug I brought with on my trip - the size I like, just over ten ounces.

I was taught that trimming the bottom of the pot was part of the balance, stand and overall design of the piece.  I enjoy trimming,  if I was a high production potter I am sure I would find it tedious after awhile.    Denice

I trim a foot ring into the bottom of every pot that I'm able to. Some form make it too difficult to impossible, but I avoid a flat bottom whenever I can. It just looks more finished.