Air bubbles inside a Saltwater tank.

[Ed Hahn]

Recently we had a member talking about putting a air line on a power head to drive air into their saltwater tank. My concern is Salt creep. If the person had corals I would be concerned with corals being affected. Can someone explain the pros and cons of powerheads with air lines in a Fish only with live rock and a Reef Tank?
Thanks in Advance,
Ed

 

[reedman]

I've heard that the bubbles irritating hard corals is a bit of a myth. I think it may be a partial truth. Here's my take. Think about a reef in the wild. When a wave crashes there are a LOT of bubbles. Yes? Many people use dump buckets and surge devices in aquariums for water movement. These introduce bubbles and the corals are happy. I think that intermitant bubbles with time enough for them to collect and surface is fine. On the other hand, if the bubbles are continuous (as with a powerhead) they might irritate a coral.

The only reason I know of to introduce oxygen this way would be if you didn't have a good skimmer on the tank. A skimmer is introducing oxygen into the water on a continual basis and should be sufficient.

 

[Ed Hahn]

Here is one I hear from time to time, Does Air driven into system by means of air pump or power head stablize the PH?

 

[reedman]

I don't know about stabilizing it, but it would certaily drive off CO2 which would , in effect, increase PH. That is if the air being drivin in is not high in CO2. This is the same principle as doing to outside air test on a water sample Ed. If you were to do this at the same time you are dosing Kalk then this might stabilize the PH a bit. If you did this 24/7 I would think it would exacerbate the issue during the lights on period. I could be wrong though

 

[MikeS]

my main concern would be any sponges on the LR...trapped air tends to kill them off pretty quick, potentialy creating water quality issues....JMHO...

MikeS

 

[reedman]

Great point Mike. I forgot about the sponges.

 

[Zephrant]

Another point- Crashing waves will cause the bubbles to move all the time, they don’t get trapped and stagnant. That is rarely the case in a tank, unless you have very heavy water flow.

I have a Cap frag in a frag tank that was near the overflow from the tank above. It collected bubbles on the bottom of the horizontal frag, and killed the tissue there.

Had they been regularly washed off, I'm sure it would have been fine.

I moved the frag, and it is recovering fine.

Zeph

 

[Ed Hahn]

Hey Zeph,
Good to see you. So direct flow of air bubbles can cause deteriation on some corals. Like Zeph said the capricornus, and Mike said definitely sponges, I want to believe most SPS are sensitive to tiny air bubbles. I would assume clams also. I am just guessing though. I have nothing to prove that. Can some one help me out please?

 

[Tsadik]

I never saw in my life reef with out bubbles the just something what reefers in home tanks think the bubbles are something bad IMO&IME that's absolutely nonsense.

 

[reedman]

I still think it is more a matter of air buildup that air bubbles. A crashing wave causes an aweful lot of bubbles to hit SPS in the wild. They seem to grow very happily. That said, the flow in the area is so high that the bubbles are driven off quite quickly and do not cause air pockets. I believe this is what Zeph was eluding to.

 

[Tsadik]

reedman if that is the case I would raise the flow in tank

 

[Ed Hahn]

Tsadik,
Do you run air with your SPS,If so do the bubbles bounce off the SPS or LPS? I use to run air in my tank. My wife liked the looks. Its my oppinion that air irritates corals at times besides causing salt creep. I want a second oppinon though. I am asking others if they had the same experience.
Thanks in Advance,
Ed

 

[Tsadik]

I never run airstone in my tank.IME the bubbles will get attached to the corals only flow can take them away from corals.

 

[Ed Hahn]

When my water is low in my sump, I get tiny micro bubbles in my tank. I immediately notice my SPS sliming or putting a defense mode up. I wonder how many others top off their tank manually and notice this.

 

[Jim_D]

I still think it is more a matter of air buildup that air bubbles. A crashing wave causes an aweful lot of bubbles to hit SPS in the wild. They seem to grow very happily. That said, the flow in the area is so high that the bubbles are driven off quite quickly and do not cause air pockets. I believe this is what Zeph was eluding to.

Thats a really well put statement.

 

[mojoreef]

What is the person trying to accomplish with putting air into thier main system?? If its a means to raise PH I dont think that is a good plan as thier are way to many cons to it.
It will irratate corals as it builds up. It will just kill your light trying to penetrate the water to lower depths, it will capture organics as form a film on the waters surface just to name a few things.
Let us know what the stiry is Ed and we can fix it up with out the issues.

Mike

 

[Ed Hahn]

This question came from a member down here in Tri-Cities. The oppinion was that a saltwater tank needed oxygen, That is true for animals and gas exchange. I agree it does need Oxygen to remove Carbon Dioxide. But the air inducted by a powerhead or a air stone is not doing as much water movement compared to a powerhead with out air line in my oppinion. I want to think of air bubble skimming protiens, I want to think of air bubbles collecting CO2 and bursting it at water surface. I see no way for proteins to be trapped. The tiny bubbles burst at the water surface to create a path for salt to build and leak water out of your tank if not stopped, I hear this called Salt Creep. The oxygen is created by water movement that prevents a stagnet water surface, good water quality. What I mean by good water quaility is water that has cycled and has very low toxins. A tank that is not concealed on the top to allow gas exchange. I wanted more eyes to evaluate this. I wanted other oppinions to so I could learn myself as well. I appreciate the oppinions and time.
thanks,
Ed

 

[dnjan]

I have a couple of airstones in the back of my tank, connected to one of those battery-powered, electricity-off-detecting air pumps. Longest it has ever run is about 8 hours. No coral damage during that time. When the power came back on, most of the bubbles accumulated under corals, etc., were removed by the waterflow/pumps.

I have also used airstones for an air-lift system in a quarentine tank. No chance of getting bubbles under corals, as the air-lift system directed the bubbles to the surface.

Salt creep is a problem. Especially in a euro-braced tank. I have enough of a problem remembering to periodically wipe the underside of the euro-bracing as it is, and that is just from the normal accumulation. I would probably be blocking serious light with an airstone running all the time.

Ed - I assume this issue came up with respect to a tank that did not have a sump (or skimmer). I think that most people would agree that a skimmer is the preferred method of aerating a tank.

Plus, if you have enough water movement in your tank, the output from airstones, airwand, etc. isn't as "pretty, IMHO.

 

[sryder]

i have a newer tank and am getting alot of micro bubbles out of my returns. i have checked all fittings for air leaks and am having no luck. any ideas?

 

[dnjan]

Do you have a skimmer? If so, perhaps the air bubbles from the skimmer aren't having a chance to leave the system before they get sucked up by your return pump.

Also, the drain into the sump can sometimes create enough turbulence to result in bubbles being sucked up by the return pump.

System details?