Aeration: pretty important

[Sk8r]

If you go to, say, Seattle Aquarium, and watch the tanks, you do notice that the ocean is not always a peaceful place. Waves roll, bubbles surge through, and currents suck everything and everybody hither and yon. Yes, there are quiet depths where storms don't reach, and quiet coves where species thrive without the action of a laundromat...

But one thing that happens in all this froth and fuss is a lot of contact between air and water. Aeration, in other words. Surging, bubbly LOTS of contact.

How can our little tanks match that?
Several ways. I"m lucky in having a 1 story drop to my sump, so returning water comes in with an air-gap and a couple of inches of fall, which is nice; but your return WILL help punch air into your water.

Another is your skimmer. The frothier the better. The more you can get a foam like whipped cream, the better.

Then there's the violence of the return TO the tank. That aerates.

A cheato ball in the sump is a great aerator. It exudes oxygen.

And a powerhead or laminar flow generator like a Gyre helps---pushing that current sideways, and clearing gunk out from under your rocks. I set mine where my fishes get a lot of exercise if they want to get up into it.

It doesn't mean, however, that your tank has to be a mixmaster. A tank can be tranquil and still have a lot of oxygenation---delivered from a sump with a good fall of water and a skimmer that froths, ---or a good cheato ball, etc. Little tanks have a tendency to be quiet tanks, because they have constraints, but if you stock with common sense you still can have healthy oxygenation, enough for everybody. It also means if you have a power-out that lasts for hours, you're going to be okay. There's enough reserve...

But while we're mentioning reserve, what DO you do in a power-out? Well, if your tank is well-oxygenated in the first place, you may have up to 8 hours of grace.
Obviously, to save you from an oxygen crisis---a generator, keeping everything going. OR---a Penn-plax bubbler that cuts on with an airhose and bubbler (discreetly placed in your display tank) while you're at the office: these go on when the power fails. Battery driven, of course. OR, if you're home, and have none of the above, get a pitcher, dip up water from your tank, stand on a chair and pour water slowly back into your tank, dip and pour, dip and pour, until what you've poured equals the gallonage in your water system. Do this every 4 hours of the power-out, day and night. Yep. I've done it: with a 130 gallon system. And it worked.

The advantage of a well-oxygenated tank is, in my experience, better health for your fish, a cleaner tank, and a good deal more grace if the power fails.

[HumbleFish]

Great write-up!

I'd just like to add that oxygen is extremely important when quarantining fish, and especially when using medications since some actually deplete O2. So, crank up an airstone or point a powerhead towards the surface of the water... anything to increase gas exchange whilst dosing meds in QT.

[hkgar]

+1 I agree completely. I also have a 1 story drop from DT to sump. Worst part is that I also have a 15 foot horizontal separation and the turns in the return from sump to DT put a lot of head pressure on my return pump (Iwaki 100 rated at about 2800 0 head) so my return flow is only about 600.

I use the Gyre but need to be careful of placement and speed or the tissue of near by SPS tends to get blown off.

If you are going to be serious about this hobby a generator is a must. I had a hurricane in Florida and lost power, no generator and none to buy anywhere, everything in the tank was dead within 24 hours.