4 ft x 3 ft x 16” cool growing terrarium in so cal, the impossible?

[itilien]

So I assume that you have some opening in the tank, because otherwise the humidity inside it will become very high and the water won't evaporate hence the temperature won't drop.

Did you have some problems with algae/slime over the wall? I suppose you did not try to grow orchids on the wall itself, as the wool is very thin.

At the moment I'm planing to make a small tank, probably something about 50x40x25 cm, in which I will use rockwool wall with thickness of about 3.5cm. I circulate constantly water through it and will try to grow pleurothallids in it. The tank will be closed and made from 4-5cm XPS foam, with front and top double/ tripple glass and I will cool the water with peltier.

The thing I don't like is that I cannot shape the wool in a way to look more natural, keeping a god waterflow through all of its volume. I suppose that if the wool is tilted, the surface layer won't have good waterflow.

[Jmbaum]

So I assume that you have some opening in the tank, because otherwise the humidity inside it will become very high and the water won't evaporate hence the temperature won't drop.
The air to be cooled needs to be brought in from the outside, because the air within is already saturated.

Did you have some problems with algae/slime over the wall? I suppose you did not try to grow orchids on the wall itself, as the wool is very thin.

I do grow orchids on the rock wool wall. Taxa with smaller roots work well, Pleurothaillids specifically. I use an aquarium magnetic cleaner for the glass. the moss out competes the algae and cyanobacteria, except under the substrate

At the moment I'm planing to make a small tank, probably something about 50x40x25 cm, in which I will use rockwool wall with thickness of about 3.5cm. I circulate constantly water through it and will try to grow pleurothallids in it. The tank will be closed and made from 4-5cm XPS foam, with front and top double/ triple glass and I will cool the water with peltier.
Because of the very small size you may just want to consider a beverage cooler bought second hand. You can use an thermostat to expand the temperature operation and get the diurnal drop in temperature. you can find them with glass fronts and peltier, heatsinks, insulated and nearly ready. I use a small compression cooling fridge that only needs to run 20 minutes over the course of a day to maintain temperature. You may be going overkill in some areas and neglecting other considerations, we have all been there.

The thing I don't like is that I cannot shape the wool in a way to look more natural, keeping a god waterflow through all of its volume. I suppose that if the wool is tilted, the surface layer won't have good waterflow.
I recommend scoring flowing lines in the rock wool to create texture and direct the water. I embedded my wall with activated charcoal and fine dark oil, it helps it look natural until the moss grows in it. The wool can take in a lot of water so it important that it is well saturated. AND just to throw another variable in the mix, black speaker fabric works really well and visually disappear until the moss grows in.

[itilien]

I have some experience with cooling:
https://scontent-fra5-1.xx.fbcdn.net...lQ&oe=6453FC35

This one is a 90 liters + 10 liters of cooling box behind it, which is cooled by a compressor from water dispenser. I control everything with arduino. But the cooling is very ineffective and the compressor is annoying me a lot. It has quite a big thermal mass inside and it is struggling to get the temperatures low enough in hot days. I made it last summer.

About the peltier beverage coolers - it is possible to work, but I need to cut the top and replace it with glass in order to install external lights. Also it needs other changes - installing a fence to hold the water, also the fan will be behind the wall... And I also have peltiers, arduino and so on. Beside that I'm an engeneer and embedded developer, so it is fun to experiment with all that. And I beleave that I can get better performance from a Peltier than in those fridges, because I can use much bigger high TDP computer processor cooler than the stock one. Plus more quiet operation because of better quality fan.

About the black speaker mesh - I don't want fabrics, because then it will be impossible to take out the plants if I want to move or split them. This is why I don't want to use hygrolon too.
About the flowing channels - Maybe they could work in a thin wool, but in a thick one I'm not so sure. I want to sculpt something more 3 dimensional with slopes

What dark oil?