What is the volume of fluid that must flow through the semipermeable membrane?

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I think this is a simple problem to solve, but I keep getting nonsense answers.

The question: two reserviors held at constant osmolarity (say 1000 mOsm/l) are connected by a semipermeable membrane. A current of 1 uA is measured across the membrane. What is the volume of fluid that must flow through the membrane?

So I have 1 uA = 1 umol/s ion flow, and 1000 mOsm/l means that 1 umol of osmolyte corresponds to 10^-7 liters of solution. So, 0.1 ul of solution is transported per second. Is this correct?

The reason I think I'm having trouble is that using my actual numbers (100 uA, 300 mOsm/l) I get very high fluid transport rates. Much higher than what is observed.
 
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Never mind- I found the error. It was in converting Coulombs to moles- I was not using the correct conversion (Faraday's constant).

1 uA corresponds to 1.04 *10^-5 umol/s of charge flux, in case anyone is interested.