After further research, I've been convinced to do away with the undergravel filter and go with a "natural system" which utilizes a .5" plenum (formerly the undergravel filter, capped), with 1.5" of crushed coral and aragonite mixed, covered with a fine screen, upon which I have approximately 55 pounds (1") of live Florida Keys sand.

Here are the pictures of my conversion.. By the way FYI, these pictures are taken with a Sony DCR-PC100 hand-held Mini-DV camcorder that has the ability to take megapixel stills. This camera is awesome, however it's still-image capture ability has been crippled by Sony and employes some real hefty jpeg compression which results in much lower-quality images than some of their stand-along digital cameras, even though the unit has a superior Zeiss lens. I think this sucks that Sony cripples an otherwise great camera to spur sales of their digital still cameras. If anyone knows how to disable the jpeg compression on the PC100 please let me know! You'll note that the pics below look pretty good - well that's because I enhanced them after downloading them from the camera.


This is the tank before the changeover. The current setup is the UGF with a Bakpak II protein skimmer, and a Millennium 2000 bio/chemical filtration unit, and a 402 powerhead. The powerhead was hooked up to one of the UGF intakes. It will now be free. That's not a weird version of a BakPak protein skimmer -- that's the flourescent hood sitting on top of it! Hehehe


Here's a closeup of the left side of the tank BEFORE the conversion. There are also 2-3 new pieces of live Fiji rock I added to the tank since part I.


Here is the half-way point in the conversion. I layed down the screen and put sand on top, did half the tank and then moved the live rock over to the other side and am getting ready to do the left side of the tank.


Here's a wider view of the same point in the conversion. You can see the progression. In the tank at this time I have 4 damsels and 9 pieces of live rock, and one starfish. It just seemed obvious to me the fish would be ok....


Left side finished. Super cloudy and very un-appealing looking, but what can ya do? You just have to wait for things to settle down. This is when I miss the undergravel filter - it sure as hell kept the water nice and clear.


I've spread the live rock back out across the tank and added a tad bit of extra sand here and there. I'll wait until things clear to see how well the conversion went...


Here's a closeup of the new substrate. It is about 4" deep, with about 30% plenum, 40% crushed coral/aragonite mix, 30% live sand on top.


Ugh it sure is cloudy....for now...time to take a break.


A few hours later, it's a bit less cloudy... I don't see all the fish... hmmmm I hope they're hiding!


The next morning, the tank is much clearer and looks a lot better. The live sand is much lighter than the crushed coral and it makes the tank look brighter.


Later in the day the tank has cleared up nicely and looks better than ever! However, I'm disappointed to see one of the blue damsels missing! I'm now freaking out thinking the poor fish got buried under the live sand but this is crazy. I took my time with the conversion giving the fish every opportunity to swim away... I still have not found the fish - I keep thinking maybe he jumped out and the dog ate him.. LOL I just don't know. I wonder if he is buried is this going to create some weird chemical spike in the tank?


Here's a closeup of the new substrate in place. Everything is looking good!

NEXT - Part III - Installing Metal Halide/PC lighting!

Part I