ok i bought a yellow wrasse today. i acclimated him and everything. then i usually feed my fish when i just start adding a new one. to decrease being terrtitorial. anyways he was lurking in the tank for good 10 minutes and eating. then after went to a smoke break then i came back all i see is a blurry water from sand. how long do they usually burrow in the sand? hours? days? or weeks?

Hours.
They burrow into the sand to sleep.

ok so just hours. but it burrow itself in the middle of the day and lights r turned on. very beatiful fish by the way

They may also burrow if scared. What kind of sand do you have? Some substrates are not suitable for wrasse diving in them.

I don't know how you know all of this stuff.

many wrasses will burrow every night just before your timed lights out - they secrete a mucus covering overnight so you might be able to spot it's location but don't disturb it - it'll come out when ready. You should have smaller grain aragonite or sand and make sure it's at least 2-3"

My older wrasse would get lazy leaning against rocks at 5pm or so then circle his sleeping area like a dog then shoot to the top of the tank and dive into bed every night at 6:30pm...

ow i have a really small grain sand. i forgot the name. its the bag live sand. and i have 2-2.5 inches of sand. so yeah its been 7 hours since it burrow and i havent seen him. it burrow like 3 pm and its now 10 pm lights off. and havent seen him. my usuall light scheadule is 12pm to 8pm. maybe its just getting used to the tank. i hope

Just give it some time. As mentioned, try not to stress it out by trying to dig it up or anything. The fact that it's eating is good.

oh alright thanks for the reply guys

How is he - I've been waiting at my computer for an update all week

I read a post recently on a reef club forum about a new wrasse in a tank emerging from the sand bed 4 days after being put into the tank and immediately burying himself. Depending on how well fed he was prior to adding to your tank, he might still pull through if you haven't seen him.

My new six line hid for a day - then came out to investigate - got wedged in a locline I had on the frag rag with zoa's growing on it - lesson learned- and had to be cut out of it! He hid in the rocks for 3+ days then came back out and is fully recovered.

they are hardy given the right import and aquarium conditions

mine sleep in sand and when first got they were under for some time but now always out and about for most part.

oh thanks for the reply guys. we'll i have to update. my yellow wrasse just bury when its sleeps now. its just the first day that i got scared cuz its the first time i got it. anyways he pop right back up in the morning and doing good. now he's scheadule is to sleep exactly 6:45 pm in my tank. lolz oh and hes always out the whole day. and getting along with my six line. and they eat like pigs.