Low iron glass

[Willito]

Does the low iron glass come in different grades or is it just one type known as Starphire. Any idea what the clearest glass is that is available for aquarium use.

[BT05]

There is another type of ultra-clear glass that is made by a competitior of PPG (I forget the actual name). In terms of grade, I'm not sure what you mean, but it does come in different thickness and can also be tempered.

I believe that the price of oil has a significant effect on the cost of acrylic. Not sure about glass, but it seems reasonable to assume this...

I got a quote from Bow Valley/Inter-American for a similar tank to yours and it was about the same price you were given. They do quality work but last time I talked to Doug he told me they were really busy and had huge orders coming in from local shops and from the US, so it might take a while if you go with them.