Their BTC/USD volume is very low, in fact, today their volume is 255BTC mostly caused by 2 volume spikes.
First spike 134.7BTC, and the second spike 41.8BTC, which totals 176.5BTC.
You sure? I just checked their 24 hours BTC/USD volume and it only shows 73BTC.
I'm not talking about BTC/ altcoin volume. That kind of volume is not relevant.
Darn! I must have looked elsewhere (probably at the amount of BTC available) — the volume you stated was rather big. The '24h volume' above the chart shows now around 62 BTC. Would be nice to see yesterday's numbers again today..