Twomixdiver:Any harm in just filling the unit, loop, et al, with clean, fresh, water to see how much it holds?
Not really I suppose, but I'd do it after my scrubber's been exhausted, or do it with the canister empty, but then you'd have to account somehow for the volume of the scrubber as well and how much water it can absorb. But I have an Evolution, which uses a smaller scrubber canister than the Inspo so I wouldn't be able to answer definitely for the Inspo.