View Full Version : Surface Agitation/Gas Exchange

03-25-2011, 02:49 AM
I've just swapped out my two Koralia 1 powerheads for a shiny new Vortech MP10 ES. I have a question about surface agitation.

When I had the Koralias, I had them pointed at eachother with upward angles in order to break the surface tension. I'm currently running my vortech on "reef crest" mode and have noticed that there's lots of movement within the tank water but substantially less ripples on the surface of the water.

I'm running a 15G nano tank that has no overflow or sump. The Vortech is the only flow. Should I be worried about gas exchange?

03-25-2011, 03:03 AM
do you run a skimmer?

03-25-2011, 03:04 AM
I run a Tunze 9002 skimmer.

03-25-2011, 03:09 AM
Skimmers perform a huge amount of gas exchange. You should be fine.

03-25-2011, 04:45 AM
I had a Tunze Nano set up on my 38G years ago and it did not raise the o2 levels enough for my bioload. The reason was because the oxygenated water from the skimmer could not escape the skimmer box fast enough since water exchange is not induced but is through diffusion over 2 pinholes at the bottom of the skimmer.

My Aquaclear provided more oxygen to my tank than the Tunze Nano skimmer.

I did not have o2 problems with any of the other skimmers that I've used (Remora, Urchin, MCE 300). Makes sense since those skimmers have pumps feeding water into the skimmer and thus displacing the oxygenated water back into the tank.

I can't speak on whether the Tunze Nano is sufficient for a lightly stocked 15G tank. It might be.

03-25-2011, 06:22 AM
Well, I've spent a lot of the night between writing my paper (which was often!) watching the tank and when the Reef crest mode increases to full power (I have it set to about 40%) it creates a lot of surface ripples. So that and the skimmer should be fine. I'll keep watch over my fish the next few days and make sure they're good, but I'm not worried about it anymore. Thanks for the replies all!

03-25-2011, 07:48 AM
for a 15 gallon I'd think the vortech on full would turn that thing to chowder.
but I got a MP20 on a 40 breeder and there's some good current from 3 inches below the water line so I'd think you're good.

03-25-2011, 07:56 AM
It's set to 40%.

03-25-2011, 06:52 PM
I love the pulse mode and find it as the best option....it cleans up your tank, agitate the water surfers, bring food to corals and wash them from mucus and stuff...