air stones

[adam riley]

is it alright to use air pump with air stone in saltwater tank?

[thegrun]

It is okay, but they do not serve much of a purpose. If you use a protein skimmer, you have all the oxygenation you need. They don't move enough water to be of any significance in a saltwater tank where you need much more flow than fresh water and unless you set it up with large bubbles, they add micro bubbles to the water which are harmful to corals.

[singold]

Yes, but keep water surface girated to allow for good O2/CO2 transfer. A powerhead pointed slightly upward helps with this.

[Aquarist007]

an alternate use of an airstone/pump is to buy the battery backup ones for about 14 dollars. In case of a power failure these will come on and last for about 8-10 hours.

[Michael]

<a href=showthread.php?s=&postid=15007413#post15007413 target=_blank>Originally posted</a> by adam riley
is it alright to use air pump with air stone in saltwater tank?

pointless really, they will just create salt creep for starters, and actually wont really add any oxygen to the tank, do you want it for asthetic reasons? or because you think it will aid oxygen into the system?

[Juruense]

An airstone in a salt water tank will create a huge salt creep problem as said above. A good skimmer will oxygenate the water as will pointing flow at the surface.

[der_wille_zur_macht]

Airstones were common on saltwater tanks before skimmers were popular. They helped then, but skimmers have made them obsolete, since as mentioned above, the bubbling action of a skimmer provides all the aeration your tank needs. Because airstones create all sorts of other problems, very, very few people use them on saltwater tanks equipped with skimmers. Even without a skimmer, you can get surface agitation through other methods (powerhead pointed at the surface to produce gentle ripples) that won't cause the same problems.

<a href=showthread.php?s=&postid=15008894#post15008894 target=_blank>Originally posted</a> by Juruense
pointing flow at the surface.

If you have a good skimmer, you actually DON'T want to disturb the surface of the tank too much, at least in the majority of cases.

If a skimmer is in-sump or has a surface skimming attachment, then you want your overflow or skimmer's surface intake to get all the nutrient-rich water that naturally collects at the surface of your tank. Breaking up the surface too much (with an airstone or powehead pointed upwards) will actually reduce the effectiveness of your skimmer in these cases.

Now, if your skimmer is a hang-on model that does not have a surface skimming intake (i.e. it sucks water from a pump located below the tank's surface), then it won't hurt its performance to disturb the tank's surface. But, as mentioned above, if you have a skimmer (any kind at all) you really need no additional aeration for your tank.

So, in summary:

1) If you have a sump or a skimmer with a surface-skimming intake, don't do anything to disturb the surface of the water
2) If #1 does not apply, you still don't need to disturb the tank's surface, unless it is so still that scum starts to form. If this happens, aim a powerhead to create gentle ripples on the tank's surface to break up the scum.

[Paul B]

What is the reason you want to do that?

[Aquarist007]

So, in summary:

1) If you have a sump or a skimmer with a surface-skimming intake, don't do anything to disturb the surface of the water
2) If #1 does not apply, you still don't need to disturb the tank's surface, unless it is so still that scum starts to form. If this happens, aim a powerhead to create gentle ripples on the tank's surface to break up the scum. [/B]

There are very little times that I disagree with you Willi but I have to on this one

The surface area is vital for gas exchange and indirectly helping stabilize the pH in your tank(by reducing co2)
The surface of the tank should be churning to do this.
Have that kind of flow on the surface directed towards the overflow or skimmer helps get organic laden water out of the display tank and to the sump/skimmer or hob skimmer.

The best senerio is a system where flow enters the tank directed towards and across the substrate. Flows upward towards the surface(accomplished by a power head low in the tank pointing upwards) and then directs across the surface of the tank towards the overflow(s) churning the surface as it does.

[der_wille_zur_macht]

Capn,

I think the dispute here is one of interpretation, not intent.

When I was suggesting people not disturb the surface, it was in the sense of having a powerhead blasting across the air/water interface, creating a wild, splashy mess. This is not warranted or desireable.

If, by "churn" we mean the natural gentle ripples created by flow into an overflow box or surface skimmer, then yes - I agree - it's important and desireable. In the end, we want "dirty" water to make it up near the surface of the tank, so it can be sucked into the overflow. This will happen naturally in most marine tanks, especially if there is a sump with a surface-skimming overflow - people don't need to do anything extra in these circumstances. If someone had a large tank with a low flow through their sump, then they might find that the natural flow into the overflow box isn't enough to keep the surface well skimmed, and in that case, using powerheads to nudge the surface water towards the overflow box would definitely be helpful.

And, regardless, I would still argue that the surface of the tank is not really critical for aeration and gas exchange when a powerful, modern skimmer is in use. Today's average skimmer sucks many times more air (in terms of litres/hour) than even the strongest air pump typically used, and creates far more gas exchange than you could realistically get by blasting the surface of your tank with powerheads or an air pump. The only tanks that typically have gas exchange issues today are tanks that are "buttoned up" much too tight - sumps in totally enclosed stands, and glass or acrylic covers on the top of the tank. Even in these cases, increasing surface agitation won't help, it's a problem of the air immediately in contact with the tank water being "stale", not a problem of air/water interface.

So I think that (for the most part) we are agreeing, just interpreting our words differently. :)

[Aquarist007]

<a href=showthread.php?s=&postid=15009196#post15009196 target=_blank>Originally posted</a> by der_wille_zur_macht
Capn,

I think the dispute here is one of interpretation, not intent.

When I was suggesting people not disturb the surface, it was in the sense of having a powerhead blasting across the air/water interface, creating a wild, splashy mess. This is not warranted or desireable.

If, by "churn" we mean the natural gentle ripples created by flow into an overflow box or surface skimmer, then yes - I agree - it's important and desireable. In the end, we want "dirty" water to make it up near the surface of the tank, so it can be sucked into the overflow. This will happen naturally in most marine tanks, especially if there is a sump with a surface-skimming overflow - people don't need to do anything extra in these circumstances. If someone had a large tank with a low flow through their sump, then they might find that the natural flow into the overflow box isn't enough to keep the surface well skimmed, and in that case, using powerheads to nudge the surface water towards the overflow box would definitely be helpful.

And, regardless, I would still argue that the surface of the tank is not really critical for aeration and gas exchange when a powerful, modern skimmer is in use. Today's average skimmer sucks many times more air (in terms of litres/hour) than even the strongest air pump typically used, and creates far more gas exchange than you could realistically get by blasting the surface of your tank with powerheads or an air pump. The only tanks that typically have gas exchange issues today are tanks that are "buttoned up" much too tight - sumps in totally enclosed stands, and glass or acrylic covers on the top of the tank. Even in these cases, increasing surface agitation won't help, it's a problem of the air immediately in contact with the tank water being "stale", not a problem of air/water interface.

So I think that (for the most part) we are agreeing, just interpreting our words differently. :)


exactly Willie--we are on the same page;) thanks for clarifiying

[der_wille_zur_macht]

Thanks for calling me out. Sometimes different people can interpret a common word like "churn" to mean totally different things, so it's helpful to be specific.

[Michael]

<a href=showthread.php?s=&postid=15009246#post15009246 target=_blank>Originally posted</a> by der_wille_zur_macht
Thanks for calling me out. Sometimes different people can interpret a common word like "churn" to mean totally different things, so it's helpful to be specific.

i didnt want to say anything, i didnt like the look of the fella in your avatar:D looks like he can bite quite hard

[Aquarist007]

<a href=showthread.php?s=&postid=15009246#post15009246 target=_blank>Originally posted</a> by der_wille_zur_macht
Thanks for calling me out. Sometimes different people can interpret a common word like "churn" to mean totally different things, so it's helpful to be specific.

I understand completly--I think that increases exponentially with the number of posts you make:lol:
I actually am glad when someone challenges what I post---I would not want someone to act on something I said because of misinterpretation(plus I or we learn at the same time too.)