Thanks again,
The input impedance is about 1Gohm/200pf. I need 1nA input, 1 Volt out. Thats a gain of 10^9. So I would need a 100M and a 10. (is that a typo above?)
Just ran some numbers and the lt1052/lt1464 wont cut it. The gain rolls off around 2KHz with a 1pf cap and 100Mohm. 0.5pf just gets 10Khz, but wont the board have more capacitance than that?
I can't seem to find a opamp that has high enough bandwidth/gain and low input base current.
