Tank Mates For A Platy?

[Byron]

I don't know where in Canada you are, but most of the country (in the south anyway) is still in summer so room temperature would be the coolest the tank would reach without a heater.  And the room is unlikely to be lower than the high 60's or low 70's, which is not problematic for platy.  So with the heater at its lowest setting or even off, you should be OK for now.  And yes, a steady temp is better than fluctuating around if extreme.
 
Pick up a couple of those mercury floating thermometers I mentioned previously; it is always handy to have a second on hand, and they are not expensive.
 
On the platy eating plants, it is normal for most livebearers (and many other fish too) to browse plant leaves.  There may be a host of microscopic food on the leaves, more as the tank ages.  The fish may nibble the leaves themselves too.  At least this is a sign of improving health.  Fish can go without food for days, so be careful not to over-feed just to get them eating more.
 
Byron.

 

[Spitter33]

I live in BC and it's been pretty hot here for a while so, and my room is especially hot. The water would definitely never get below 70 in my room. So I'll probably leave it at that until it's all sorted out. 
 
I just looked up what a mercury floating thermometers is, turns out that is what I have! But I'll grab another just in case this one is somehow faulty.
 
Could they be acting weird due to there only being 2 of them? My plan was to get 2, wait a week, then add another with another plant. I just didn't want to add all 3 at once since I'm trying to do a silent cycle, didn't want the ammonia to spike up. 
 
They're swimming around a bit now, they never leave each others side so I'm wondering if they'd be even happier with a third. But at the same time if there's something wrong I don't want to add yet another fish to this mess! 

 

[Byron]

I live in BC and it's been pretty hot here for a while so, and my room is especially hot. The water would definitely never get below 70 in my room. So I'll probably leave it at that until it's all sorted out. 
 
I just looked up what a mercury floating thermometers is, turns out that is what I have! But I'll grab another just in case this one is somehow faulty.
 
Could they be acting weird due to there only being 2 of them? My plan was to get 2, wait a week, then add another with another plant. I just didn't want to add all 3 at once since I'm trying to do a silent cycle, didn't want the ammonia to spike up. 
 
They're swimming around a bit now, they never leave each others side so I'm wondering if they'd be even happier with a third. But at the same time if there's something wrong I don't want to add yet another fish to this mess! 

 
I cannot say that all of these floating thermometers are without fault, but I have four that seem OK and when I have two in the same tank (which I sometimes test) they read the same.  I would be inclined to think the heater is the piece of equipment that is not reading true, but as I think I mentioned previously, this is common with many heaters and as long as it is consistent it is OK; just set it lower at whatever setting will give the temperature you want according to the thermometer.
 
On the fish, I would not add another until these have settled and begin to act more normally.  If they are improving, it may have been an acclimation issue, with differing parameters.  Just observe them carefully.
 
Byron.