The 7  beginner sites below all meet conditions 1 & 2 unless the wind/swell is Southerly , but factor 3 is more complicated.  ‘Viz’ is generally best (all other things being equal) in the reserve area:

1. After three continual days of slight swell (< 0.5 m) at the site. Our Island Bay Divers front page shows conditions for the last 3 days.
2. Sunny days. Viz is usually best when the sun is directly overhead (mid-day). 
3. Offshore wind - therefore a northerly wind is best for the reserve area.
4. Spring tides (at ‘no’ or ‘full’ moon). Tide times and moon phases for the year are on our link's page.
5. The day’s best viz usually starts about 60 minutes before high tide running through to 60 minutes after.
6. A sheltered site with a rocky, weedy bottom.
7. No plankton blooms (usually only a factor in summer with rising water temperature).

Note visibility is a ‘moving target’. Given the mix of 7 factors listed above, viz will change through the day - just like the weather at the surface of the site.

It takes at least three days of no swell and an offshore wind to raise the viz to the level of 'good' in the reserve, but it only takes an hour to move this good viz to 'bad' with a change in swell and wind.   
Stay out of 'white water' zones where swell & surge turn the water to soda bubbles. Swim out to a deeper depth to escape these zones.   

Divers have a thousand ways to measure visibility. Plus what's good viz for one person can be bad in another's opinion - it's subjective.
However, a good universal measure is the 'vertical' measure of viz. It needs a depth gauge or a wrist ‘computer/ watch' to be accurate. The best way is for skin divers to swim out until they can just see the full detail of the bottom. They then dive down with a depth gauge or computer/ watch and record this limit’s depth. The depth is the ‘viz’; free dive watches currently cost around $350.

If you want to find what the conditions and visibility are today in the Wellington Taputeranga reserve you can go to the home page of www.ibdivers.co.nz – updated daily conditions reports are listed on the  'what's new'  column halfway down the page. This lists  wind speed & direction, visibility, surface weather, sea state, swell height, pollution warnings, high tide & sunset time  plus 7 day forecasts for 8 Wellington region sites outside the marine reserve.

You can make your own assessment on the sea state by going to our link's page web cams section - mid page. Click halfway down the links page, go into the web cams section, click Victoria University's ‘Island Bay cam’ - this shows surface conditions real-time for ‘Island Bay’. If you want to see what the visibility is like in real time,  go to the web cams section of the links page & click on Seesea's web cam for a view of the clarity today.
NB. Unfortunately at the moment, both cameras are offline; we will advise through this site as soon as these come back online.