The Semi Official VGChartz Minecraft Thread

[Final-Fan]

OK, I'm doing some extensive underwater tunnels, and I think I have a pretty good technique.  So I figured I'd share it. 

Step 1:  Create reed beds.  This is just dirt and trenches.  On the ocean floor, generally dirt already,you'd have the choice of adding a raised bed or digging the trench.  You could have two dirt for 1 trench (TRRTRRT etc.) but in my case the tunnel size meant RTRTR was fine. 

The pumpkins are there at intervals for lighting and the rest of the row is dirt as well. 

[edit: TinyPic is dead, long live Flickr. Sorry, but my Minecraft screenshots are now tiny/blurry for some reason when embedded.  Please click the Flickr link accompanying each photo for larger version.  Original links for insanity posterity: http://oi54.tinypic.com/2z7gbkk.jpg ]

Preparing the sea floor for planting rows of reeds

Step 2:  Add the reeds, and add a row of dirt in between the bottom reeds NOT IN THE TRENCH.  If you fill in the trench the reeds become unstable and will uproot.  The objective is to fill the non-reed rows to eradicate the water but we'll see later why we are only adding one piece of dirt.   In this case I wanted 3 spaces of air above the pumpkin, so that's how tall the reeds are. 

[ http://oi52.tinypic.com/wqpm3b.jpg ]

Reeds are planted, and a row of dirt is between the reeds at reed level (water below for the reeds)

Step 3:  Add the walls and ceiling, and add sand on top of the dirt between the reeds.  You can add sand above the pumpkins too, or do it in cleanup.  Just remember that if you add sand you will no longer be able to move freely in that row anymore. 

[ http://oi52.tinypic.com/35jge9l.jpg ]

Enclosure is built, and sand replaces water above the dirt rows. The only water left is now in the trenches watering the reeds and directly above the pumpkins. 

Step 4:  Now that the tunnel section is enclosed and the water is more or less eradicated, start digging the dirt.  The sand will fall into the trench, destroying the water there as well.  The reeds will automatically pop out.  This is the reason why this technique is better IMO than just filling it entirely with sand, and of course using the reeds as an air supply isn't bad either. 

I haven't tried the "fill it with wool and then burn it" technique, but I can see why people would like that.  Wouldn't help you breathe though. 

[ http://oi56.tinypic.com/rw2r0l.jpg ]

Dig the dirt and the sand will destroy the remaining water. (Fill in the areas above the pumpkins as you go to manually destroy that water.)

P.S.  Reeds can be manually built to arbitrary heights, so this would REALLY save effort in a large space being built underwater as compared to straight sand.  But on a large scale a wool-reed combo might be most rewarding. 

P.P.S.  In large (high) spaces, it might also help to use a different water supply strategy: 
XXOXX
OXXXO
XXOXX
Because you'd want to maximize reed columns vs. sand columns.  But for tunnels I don't know if it's that much better and it's not quite as mindlessly easy. 

P.P.P.S.  Heck, I just thought of an easy way to combine wool and reeds.  Just do the plan I am doing for the tunnel only instead of dirt/sand just use wool!  [edit: and one sand to kill the trench water, but you might have to put it in the middle?  I don't know if falling sand puts out fires.] For this you'd want to make sure to fill in above the pumpkins so the leftover water doesn't douse anything. 

Last edited by Final-Fan - on 22 September 2019