eruptions from my sand?

[lazarus]

i have had my tank up 2 mos now and alls well (115g FOWLR) but i noticed some bubbles coming up from my sand bed in different spots. they seem to erupt from only a couple of locations and only every few minutes....can someone tell me whats going on? is this a product of some anaerobic activity? or...something serious? thanks in advance!

 

[spitfire]

Originally Posted by LAZARUS
i have had my tank up 2 mos now and alls well (115g FOWLR) but i noticed some bubbles coming up from my sand bed in different spots. they seem to erupt from only a couple of locations and only every few minutes....can someone tell me whats going on? is this a product of some anaerobic activity? or...something serious? thanks in advance!
Could be anaerobic activity, which is good, so long as it doesn't get disturbed.

If it does get disturbed, the bacteria will release cyanide and everything in the tank will die.

 

[brainrush]

I don't agree with SpitFire's post.
Bubbles from the sand are TOTALLY natural and just show that your sand bed is doing what it is supposed to be doing. The bubbles are gas being released as the bacteria in the sand bed digest the Nitrites...or is it the nitrates. I can never remember. Regardless, it will not release cyanide in your tank if disturbed.
It is true that it is not a good idea to stir a deep sand bed becuase that can cause an ammonia spike, but never heard of it releasing cyanide. Not sure where SpitFire got that info...

 

[murph]

Cyanide in deep sand beds??? Well I have heard a lot of myths and misconceptions when it come to deep sand beds (and this hobby in general) but I think this one takes the cake.
Possibly getting confused with black pockets of sulfur hydroxide that can form in deep sand beds and even these are of limited risk. The notion that the slightest disturbance to deep sand beds is going to cause some sort of catastrophe is also myth.
I can tell you from personal hands on experience with my tanks and others that deep sand beds, even ones with obvious sulfur hydroxide pockets can indeed be disturbed and even removed with fish and corals present in the system.
The most likely bad effect of a large disturbance/removal of the sand bed is a nitrate rise and or possible mini cycle when a large enough amount of sand is removed or turned over to upset the bacteria population responsible for the conversion of ammonia and nitrites. The nitrate rise would come from stirring up the nutrient sink that all sand beds become in one degree or another.
As far as your question laz; if your tank is relatively young and has a shallow sand bed the bubbles you are seeing are more likely the beginnings of some sort of algae or cyano growth on your sand bed. If your tank has a deep sand bed it could indeed be the DSB exporting out nitrates. Lets hope its the second one :joy:

 

[lazarus]

thanks all....i heard of the risk of "crashing" a tank when disturbing the sand so i have been careful to vacuum only the surface of sand...as for DSB i tried to get 3 inches total but i think i came up a little short. still, no livestock has dies mysteriously since i started seeing bubbles several days ago

what i can see in the front of my tank is that the sand bed is getting a purple hue to it under the surface. can you tell me what that is all about?

 

[murph]

It sounds like you are starting to get some cyano growth which could be the source of your bubbles also. If it is it will become unmistakable with patches starting to grow on the surface of the sand bed and most likely the rock also.
In the short term get as much oxygen in the water as possible (cyano hates oxygen saturated water) this means increasing surface agitation as much as possible with power heads in main tank and sump if you have one. Enclosed sumps or wet drys wont work for this. Surface agitation has to be in open air to allow for gas exchange.
Keeping nutrient sources low with water changes and a well functioning skimmer and cyano worries should go away.

 

[lazarus]

could you tell me more about what "cyano" is???
i am getting some brown patches on the sand surface and this purple tint is underneath. i know i could use more flow (i am at about 1000gph on 115g tank), but all other levels in my tank are stable (pH, ammonia, nitrates and calcium). My temp has been running high due to weather (81-84).
is this cyano a serious threat??? :notsure:

 

[murph]

just click this link to use the search function on the forum
https://forums.saltwaterfish.com/newsearch/?search=&type=all
Then type in cyano or red slime over on the left field to get a number on threads on cyano and methods of getting rid of it.
Like I said and one method that gets ignored or confused with adding flow in general to the tank is to get as much oxygen in the water as possible. Especially when temps start to rise.
Cyano is most dangerous when large amounts are present and chemical removal products are used without manually removing as much as possible. The die off and upset of bio filtration that is possible when using these products can lead to water quality problems. For the most part its just ugly.
Resort to products like Red Slime Remover as a last resort only and have plenty of change water available for after use water changes.

 

[salty cheese]

The bubbles are most likely nitrogen, your sandbed hard at work.
The brown sounds like diatoms and will eventually disappear and the cyano under the sandbed IMO is not a big deal.