Re: nutrient diffusion into substrate

>I think that until someone (better yet, a number of someones) set up side by 
>side duplicate tanks, one with laterite and one with vermiculite, and run 
>these tanks in the same manner for _at least several years_ we will not know 
>the answer to that question.

Ok, you've talked me into it.  

When I get the 40 gallon that will soon come into my possession, I'll set it up 
as a Webb-Dupla tank with a laterite-sand lower and my slow RUGF design.  I'll 
use four bulbs for it just like in my 55.  After setting it up, I'll tear down 
my 55 and set it up as a Webb-Kelly tank, minus the peat.  I a few years, I'll 
let you know (but I'll probably move first and have to tear everything down.

On a side note:

I have a 50 gallon short with a broken bottom.  The glass in the bottom is 1/2" 
thick and is prohibitively expensive to replace.  I'm planning on setting this 
tank up as a paladarium (3" substrate, 3" water).  I priced 3/8" glass and 1/4" 
glass.  The 3/8" was about $90 and the 1/4" was about $35.  

I'm considering the following:

1:  Just use 1/4" glass for the floor of the tank.

2:  Laminate two 1/4" plates together.

3:  Laminate four to six 1/8" plates together.

4:  Forget it.

Any sound advice from the glass experts on the list?

David W. Webb
Enterprise Computing Provisioning
Texas Instruments Inc.
(214) 575-3443 (voice)  MSGID:       DAWB
(214) 575-4853 (fax)    Internet:    dwebb at ti_com
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