Some Help with a Tomato Experiment, please!

I'm pretty new to gardening, am limited with the amount of sunlight I can get because I live in an apartment building with limited space outside. But I've been trying my hand at "upside down"/hanging tomato plants and have to admit, I don't know much!

I've been doing a kind of experiment with three different tomato plants.

1 plant: in complete, regular sun
1 plant: in the shade with sun provided by a "Sunflower Home Heliostat" (it's basically a mirror that has a sun tracker so it can provide consistent sunlight all day)
1 plant: gets afternoon sun but is otherwise in the shade

What I've found is the regular sun and mirror plant have flowered at about the same rate, and the fruit itself has grown at about the same rate -- but the mirror ones are actually bit larger. I'm not sure if this is due to the more consistent sunlight or if it might have to do with, maybe, the amount of fertilizer the plants are receiving (the one with the mirror is farther away from my building so it doesnt have runoff from the roof pouring through it in the rain... which could be washing away fertilizer or something), or maybe even pollination for the plants, because they're in a slightly different locations so maybe the access to them by bees or something varies enough? Maybe I'm just over thinking things... And then the plant that only gets afternoon sun, I've been struggling with overall.

I guess I'm just wondering if anyone has any thoughts on:
1. using mirrors to increase sunlight to plants in general and on tomatoes specifically - is this good, bad, effective?
2. how much sunlight tomato plants actually need
3. how much fertilizer should I be using? if anything?
4. do I need to pollinate the plants myself somehow?

And just if any experienced tomato growers might have any explanations as to the results I've been experiencing.

I'd appreciate any thoughts/explanations/comments. Thank you!!

Hi sara
First, well I see that you live in MA, I think is Maine, its to late for you to get tomatoes. Second, that upside down stuff is a ripoff money, the plant is goint to follow the sun and it will go up to catch it. I never heared anything about using mirrows,
Just lights. Tomatoes need temp above the 65 night time and in day time up to 90 f. After that if its cold the plant gets stunt and turns purple (leafs) to hot and stops producing bloms, drops them and stops producing licopene (red color)
the best tomato w short time to mature is early girl, I had it and it was done by march this year, I planted in march (ground). I live in Texas, and this year I planted a lot of tomatoes lol different kinds, nah but the
Jubile were yellow but hollow no taste, a homestead uff waste of money, the best ones were my Roma and the Early Girl. Now tomatoes can be determinant and indeterminant, the first one only grows to a determinant size. The other it just keep going! For you situation buy the patio or husky cherrie tomatoes you can bring them inside and use grow lamps. Ohh forgot tomatoe needs 8 hours of sun light!!

I think the upside down planter is a very good gardening concept especially for those who living in a tight space. At least you know that you're already on the right track.

Love the mirror idea, keep us updated on the progress of that, how that plant grows compared to others.

flushing of nutrients in a tomato pot is a big problem. This could cause lots of issues. They can become deficient quick.