Re: Aquatic Plants Digest V1 #249

> From: Eric Neustadter <ean at primenet_com>
> Subject: When to add crypts?
> The Optimium Aquarium recommends avoiding crypts until the 3-month
> point, and I'd like to hear what others feel about this.

This is to make sure that algae is suppresed during startup by
whatever means fast growing plants seem to suppress algae.  If the
tank is not prone to algae, go for it. 

> From: Bob Woolley <macaw at tiac_net>
> Subject: CO2 Reactors
> I'm constructing a cO2 reactor similar to the high priced ones sold by
> Dupla, Sandpoint, etc. I have it rigged so far so water enters the top
> and exits the bottom. CO2 will enter the bottom, thus creating a
> counter current flow. Is it necessary to have some kind of vent at the
> top to release trapped gas??

If the design is such that CO2 will collect at the top, a manually
controlled vent is a good idea.  In this situation, other gases
dissolved in the water may also collect in the gas bubble area.  With
a constant flow of water and CO2 this might not be a problem.  A
simple "bell" type reactor will need to be vented every so often
(maybe each day).  

BTW, the high priced reactor sold by Dupla has a venturi at the top
for mixing CO2 and water, producing very fine bubbles. 

> From: Zon Hisham <ittv3 at aimsvan_aims.com.my>
> Subject: 1) C02 Controller   2) Heating
> 1) My C02 controller is very sensitive to the switching on/off
> of the house flourescent tube. When the controller is
> injecting C02 with the red LED on, and then someone switches
> off a light, the C02 controller will follow suit. Have tried
> to use voltage stabilizer on the controller this morning but
> with no effect. Any idea?

CO2 probes are very high impedance devices and are easily affected by
any stray electrical impulses.  I assume it corrects itself in a very
short time?  Either ignore it or try adding a "grounding probe" to the
tank to minimize induced voltages.  A grounding probe is a
non-reactive piece of wire like stainless steel or titanium that is
connected to an electrical ground. 

> 2) Room temperature 30C. But we all know that aquatic plants
> would best be in 27-28C. Would I be crazy to set the heater stat
> at 31-32C so that a nutrient spring develop in the gravel?
> Or should I just make do without UGH? Anyway now is the hottest
> month in Malaysia. I suspected the room temperature to fall
> in the region of 27-28 in a couple weeks time. 

I would wait until your ambient temperature drops.  

George in Balmy and Dry Northern Colorado