# Best Aeration Option??



## frank testagrose (Sep 22, 2010)

i have a 125 gallon with 2 fluval 405's on it, what would give me the best aeration and water movement- a koralia evolution pumping 1200 GPH or and aquaclear powerhead model 70 or 110.
with the AC do you hook that up to an air pump?? how does that work exactly
and if i'm using the koralia its really just going to move water and not aerate the tank , right??
thanks for the replies


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## fox (Jun 11, 2009)

For aeration put a spray bar on one of the returns and point them upwards to disturb the surface. :thumb:

The AC powerheads are more of a jet pattern when compared to the koralia. Not that thats a bad thing but something you might want to consider. I have a few AC powerheads and use them in some of our tanks with the quick filter attachment.


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## frank testagrose (Sep 22, 2010)

just ordered a spray bar on ebay.i'll leave the other one just the regular jet that comes with the filter. i'm torn between the koralia and the AC, do you hook an air pump up to the AC to make the bubbles? If the spray bar makes alot of turbulence maybe i'll just get the koralia and point it towards the rear of the tank, unless i hear some more advice against it.. thanks


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## fmueller (Jan 11, 2004)

Both, the AC powerheads and the Koralia, are simply submersible pumps that you hang into your tank. They can be used for aeration if they are equipped with a venturi valve. In a nutshell, the pump pushes the water through a constricted section of pipe. According to the laws governing fluid dynamics, the pressure is lower in the constricted section, and this is used to suck air into the water that will end up finely dispersed in your tank. This will allow lots of oxygen to be dissolved in the water.

In other words, no air pump is required to push air into the water, but through a clever setup a water pump creates a current in the tank, and at the same time sucks air in from the outside that is dispersed into the water.

The powerheads and the Koralia pump presumably come with venturi valves. Alternatively you can buy a venturi valve for around $10 (diffuser), and use it as outlet for your canister filters instead of the spray bar you just ordered. I'd recommend the latter and ditch the spray bar, because a diffuser will give you the most bang for you buck - not only in the purchase price, but also on your electricity bill for years to come :thumb:


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## frank testagrose (Sep 22, 2010)

where would i pick up a diffuser for the outlet for my fluval 405????
thanks for the advice!!!!!!!!!


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## frank testagrose (Sep 22, 2010)

or a venturi valve...and how does it hook up to the outlet pipe?


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## fmueller (Jan 11, 2004)

For our purposes diffuser/diffusor and venturi valve are different names for the same gizmo. I am not 100% sure of the diameter of the outlet hose of a 405, but this diffuser fits most canisters - or can be made to fit.

You push the outlet hose right over the intake of the diffuser, in the same way as you would with a spray bar. If the hose seems a little tight, dipping the end into hot water will make it soft and flexible, and you can push it over a pipe twice its diameter. If the hose is too wide, put a short piece of thinner hose over the pipe first to make it thicker. Hopefully all this won't be necessary, and it will fit right away.

Best of luck!


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## fmueller (Jan 11, 2004)

OK, I just did some further research. According to Petsolution's Canister Filter Comparison Chart, the Fluval 405 has a outlet hose size of 16mm or 5/8" (same as an Eheim 2260). That equals 0.625", meaning the standard diffusor for a 0.35in/0.50 inch hose is a bit small. The larger version of the diffusor for a 0.65in/0.90 inch hose is a PITA to find - I know, because I needed one for my Eheim 2260 - but I just tracked it down at AnimalWorldNetwork.com. Not a retailer I am familiar with, but might be your only option!


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## frank testagrose (Sep 22, 2010)

fmueller-----You Are The MAN


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## frank testagrose (Sep 22, 2010)

just ordered that diffusor from eheim, thanks for the advice everyone.. especially fmueller, nothings better than having someone do basically everything for you


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## frank testagrose (Sep 22, 2010)

sooooo....the company that i ordered it from didn't have it in stock anymore so i went to eheimparts.com and they hooked me up. this diffusor is fantastic


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