I have been using a couple of Spider-Farmer SF1000 lights over my succulents and cacti for about a year now. Plants are all alive and healthy but I'm not getting the sort of growth that I got when I had them at our previous house (they got a ton of natural sunlight there). I'd like to pick up some sort of light meter to see exactly what readings I'm getting so I can modify as needed...

My questions are:

1. Could anyone recommend an affordable light meter for this? A quantum PAR meter... Or whatever I'd need to accurately read all the relevant parameters.

2. What are the key parameters to check - PAR, PPFD, Lux, Foot Candles?

3. Where SHOULD those numbers be for succulents and cacti? In my collection are a few Crassula (jade) sp., Pachypodium, Euphorbia and on the higher end for light requirements, a totem pole cactus (Pachycereus schotti).

Thanks in advance!