[APD] Re: a reposting of my plant situation

["Chuck H" <grendel at usit_net>]

Hubbadubba wrote:

> Hi all, I 'm going to repost this question in the hopes that i get more
> responses  =)  
> 
> So here's my question.  By the grace of God, I was able to purchase two
> used 20 gallon acrylics for a good deal.  I also was able to find custom
> sealife smartlite 2 x 65 watt 4 foot hood.     Here's my plan.  I will be
> placing the 2 tanks next to each other and that will make it 4 feet long.
> So essentially, each tank will be getting one 65 watt bulb over it.. I am
> wondering if this hood, if placed over the middle area,  would be
> sufficient enough light to grow plants like   glossostigma, dwarf
> hairgrass, stargrass, pearlweed.    
> 
> here's some more info:   DIY Co2,     i'm using a penguin 660 powerhead
> for circulation,  no other filtration,   one tank is ecocomplete substrate
> 100%,  the other is a flourite gravel 50/50 mix.   
> 
> my water parameters from tap   are   ph=8 , kh= 7 ,   gh= 7,  nitrates=0,
> phosphates =0 calcium= 50 ppm   magnesium = 25 ppm   iron = 0 ppm   
> 
> the reason i'm asking this question is with previous experience using 2 x
> 65 watt coralife fixture over a 40 gallon long, I've had problems with
> rotala rotundifolia stems rotting if they are shaded the least bit...  i
> don't want to end up placing a big order of glosso and hairgrass and
> stargrass and pearlweed and then have them melt on me from lack of light. 
>  Any suggestions or comments are appreciate.. Thank you.


A single 65W lamp over a 20 gallon tank can give you enough light to 
grow what you want, but light distribution (or light spread) will be 
much more of an issue than it would be if you had multiple lamps, and 
keeping tall plants pruned to prevent shading will be more critical.  
Placing the fixture higher above the tank can help alleviate these 
problems, as can a wide reflector.  I haven't had the chance to check 
out a Smartlite fixture yet, so I'm not sure how they're set up.  The 
good news is that you can always add more light if you feel it's 
needed.

As for the problem of your Rotala stems rotting, that often has as 
much to do with nutrient dosing and balance as light IMHO, though 
poor lighting can definitely cause problems.  I've found that 
chronically low iron (and perhaps other traces) will cause some 
plants to rot at the lower stem or at the base of the leaves.  I've 
seen it in Rotala, Ludwigia, Hottonia, chain swords (leaves rot at 
the crown), some Crypts (continuous meltdown of older leaves), and 
probably others that I can't think of right now.  I'm certain that 
the rotting problems my plants had where not light related since I 
was able to correct the problem without changing the light setup.  
Mileage may vary, but it's something you might want to consider.
--
Chuck Huffine
Knoxville, Tennessee

_______________________________________________
Aquatic-Plants mailing list
Aquatic-Plants at actwin_com
http://www.actwin.com/mailman/listinfo.cgi/aquatic-plants