I'm trying to work out how to estimate which days will have good vis around Samui. I know most people who dive in this area do so around Koh Tao, being surrounded by deep water and far away from mainland rivers means the water is much clearer.

I free dive around samui but some days you can barely see your hand infront of your face, other days you can get 5 or 6 meters vis (this is very rare though). I was wondering if anyone knew how to guess which days and times of days will be best. High tide, low tide, full moon, half moon?

I'm fed up with getting all my gear ready and making the effort only to get in the water and realise you're wasting your time!

I know when it rains there is run off which is dirty and makes the vis very poor, also rough weather stirs up the bottom and likewise cuts down the vis. Other than that I know very little..........

Can anyone shed some light?

Edited December 5, 200817 yr by womble

maenam isn't worth coming in 6 months i'm swimming there, the water is never clear.

from my experience, chaweng is clear at the beggining of the beach road on the top, you'll have to turn left and go down along a small street to reach the place i'm talking about (you have a place with rocks so it's calm and full of life), lamai(near the grand mother rock) an chong moen(but you have something in the water that ites you every two minutes there)

unfortunately those period of clear visibility don't last a lot and samui is very bad for anyone enjoying diving, the period where i saw the water clear was during the hotest season, march to may.

From what i've seen the clearest spots are eigher end of chaweng beach, eigher end of lamai and coral cove. The north has always seemed murky to me, bophut, meanam, can't even see your hand.

Womble

Usually the best time is around slack water when high tide has just come in, little water movement means all the particles are stirred up less and in theory settle making the water clearer. Tide times can be found at thai hydro department or on google.