I thought I was doing ok with this pink aglaonema but, *sigh*, looks like I failed again. There was a bit of root rot. I've invested in a soil moisture meter to be sure I water when it's the right time and yet looks like I've overwatered. I was so glad with this lil plant and now it's ugly. I'm feeling very discouraged. I've put so much time, energy, money, effort, HOPE, into all this, only to fail again. 
Attaching pics of a not yet dead but barely surviving money tree, not yet but barely surviving australian chestnut, probably soon to be dead already curling up calathea, definitely not thriving monstera with black splotches on its leaves as well as pale and floppy new leaves that are not unfurling.
I know they don't get much light, as they're far away from a west-facing window, but I can't really put them anywhere else as this is the only place my cat can't access (thanks to the fish tank)
I also have a peace lily, another aglaonema, a yucca and a mini dracaena in an empty fish tank under some lights meant for the fish tank. I bought these plants not too long ago and this is them in isolation. Now I don't know if it's because of the fish tank trapping the moisture in as there's not that much air flow in it, but the soil gets moldy. The soil tends to get moldy everywhere else in the flat, which is an at least 100yo place with no heat insulation so we do tend to get mold on the walls and around the windows. 
I don't know how to accommodate for all this.
I used to do top watering, now I try to do bottom watering but I mustn't be doing it right cause the soil gets so soggy even days later.
I thought the soil moisture meter would be a game changer, but it obviously was not. 
Yesterday I bought 2 3-head grow lights which I don't really have the room for but I'm thinking this is last resort. I don't know what else to do
do, I feel like I'm out of ammo.

So tired of failing with nearly every plant