Re: [AGA-Member] Re: UH heaters

[Heather J Gladney <hgladney@comcast.net>]

GG Info wrote:

> I guess I'm just not convinced of the value of a UG heating system, most of
> the tanks I've seen don't have them and still look amazing.
>  
As with prior comment, I'm in just too hot a climate for it to work for 
me.  My CF lights that keep it that way.  Can't afford a chiller, I've 
got to fight to keep the tank down to 76 degrees F, and it visits 80 
regularly.  Briefly hijacking the thread here, yes, I was thinking about 
discus, once I get the tank's nutrient levels sorted out.  But I don't 
know if discus can handle 10-12 ppm nitrates, and I hate to put an 
animal into too tough an environment for them.

> I understand the theory, just not sure if it really applies in a micro
> system like a planted tank.
>  
Per George Booth's older website (still good reference, too), his 
Barclaya (orchid lilies) really liked it, made a huge difference in a 
100 gallon or so tank.  This doesn't surprise me, as there's always one 
plant that likes special conditions!  But he's in a cool climate, too.

> I have read from several sources including Don Matakis that it is important
> to have a closed bottom stand to prevent the substrate from cooling, but all
> my stands have open bottoms save for one, and that one gives me the most
> trouble.
>  
You could put up sheet foam (such as those big rolls of 1/2" or 3/4" 
foam you cut with scissors from places like Tap Plastics) as insulation 
underneath, if you were worried about it in cold nasty weather, when the 
house is cold for weeks.  I put up a slab of it along the back wall to 
fend off heat radiated by an exterior garage wall.  Yes, it gets that hot!

> I have considered that having the bottom of the tank exposed does create a
> temperature differential between the water column, and as long as the
> substrate isn't cool enough to affect the roots, would actually create a
> limited convection current along the same theory of heater cables.
>  
I would think so, but I'm not an authority on it!  I've seen comments 
that the slow oxygen flow pumped in by the plant roots actually creates 
convection currents without any need for more substrate circulation in 
most good substrates.  And I'm told that you may want small pockets of 
anaerobic zones where iron oxides are reduced to more available forms.  
The roots forage in after it, protecting themselves with oxygen flow 
from any contact with hydrogen sulfide.  You'd think this would also 
swap the iron back to unavailable oxides.  So I don't know whether the 
roots have some sort of time gradient there, just enough time to drive 
off H2S, but not enough for iron to oxidise before they pick it up.

> Any thoughts?
>
>
>
>  



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