[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: Aquatic Plants Digest V4 #1610

Thanks Roger!

I'm going to see if I can maybe slow down the rate of flow and check out
Tom's external reactor stuff (previous posting)... I've got good covers
on the sump, but I suspect I could seal it even better.. :)


> Date: Wed, 13 Feb 2002 12:12:15 -0800
> From: "Roger Gordon" <rgordon at tns_net>
> Subject: Re: Aquatic Plants Digest V4 #1609  CO2 in Sump
> Dear Greg,
> I have a wet/dry on my 100 gallon tank.  I inject CO2 via an 
> Eheim diffuser in the wet/dry.  Initially, I had the diffuser 
> in the half of the wet/dry that held the bio balls.  That 
> made cleaning the top of the diffuser very difficult so I 
> eventually moved it to the sump portion of the wet/dry.  I 
> have tight lids on the top of the wet/dry so that the CO2 
> that is not immediately absorbed in the water stays trapped 
> in the wet/dry to be absorbed as the water tumbles through 
> the wet/dry.  What I have found critical to maintaining high 
> CO2 levels in my system is controlling the rate of flow 
> through the wet/dry filter.  Even though I have the return 
> spray bars under water, if the rate of flow through the 
> wet/dry exceeds a certain rate, the CO2 is driven off very 
> quickly.  Surface agitation is one factor that drives off 
> CO2.  With the return bars under the water that is not too 
> much of a problem except at maximum flow rates.  However, in 
> my system, whether the water flows smoothly and quietly into 
> the built-in prefilter box or cascades loudly into the 
> prefilter box makes a big difference in the CO2 level.  
> Apparently, the water cascading into the prefilter box drives 
> off the CO2.
> To control the rate of flow through the wet/dry I have a ball 
> valve after the Eheim 1060 hobby pump which I use as the 
> return pump.  The Eheim can have its current flow restricted 
> without any reliability problems.  Not all pumps are built that way.
> By reducing the flow of water through the wet/dry I keep the 
> water level in the wet/dry at least 12" deep (which allows 
> better absorption of the tiny bubbles from the diffuser) and 
> I also minimize the CO2 lost due to surface agitation and 
> prefilter tumble.
> Try reducing your rate of flow.  It works for me.
> Best Regards,
> Roger Gordon