This may sound stupid but where does the red, green and other marine algae come from in a tank.
1. Is it on the fish you buy
2. Is it in the salt mix
I know its a sign of a normal tank but its not like you run out and buy ALge seeds for your marine tank. It sort of just pops up on its own.
Some of the reds actually look pretty decent in small quantities.
I'm guessing its on the fish. So with each fish you not only get the fish but also the needed bacteria for Ammonia/nitrite reduction plus a few types of algae. Sometimes some ICH to boot.
If I had to guess, I'd say it's dormant in/on the LR until conditions are suitable. There are also airborne spores, although I don't know if that covers marine algae as well as FW.
I would definitely agree with pearson on this, that it leaves spores, or hidden patches on the LR you buy. As well, it could be in the air and it couold also be on the fish you buy, like you said goblin.
It seems certain there would be traces on any live rock. I think perhaps his question is how does algae grow in a new, empty tank? I can state from experience that a brand new tank with no life, just water and salt will grow brown diatoms. I'm sure if you add a fish or other specimen, there's some algae spores in the water it's bagged with.
Was it Pascal that had to put rotting meat into a jar covered with cheese cloth to prove spontaneous life didn't exist?
I wonder if diatoms have a dormant state? Possibly they come in the sand? Other algae for that matter as well. Since it's dredged from the ocean, I wonder if it's just dormant waiting on good water, light and food?
Many life forms exist in different forms throughout their life cycle, including forms that will allow them to persist through tough environmental times (like being put in a box and shipped half way around the world)
A quick google search of "life cycle of marine algae" turned up these things that might be helpful:
Here a link to an example of the red algae life cycle.
"Human subtelty will never devise an invention more beautiful,
more simple or more direct than does nature"
- Leonardo Da Vinci
"I am made of the dust of the stars, and the oceans flow in my veins"
-Neil Peart
"The strenuous and dogmatic are the moral enemy of the good. They demand that we believe the impossible and practice the unfeasible" - Christopher Hitchens
Algae exports nutrients like nitrate or phosphate and that is good. But some like HA can overgrow corals and that is not good. Algae is part of the cycle of any tank and you are going to have to battle some of it. The key is to not introduce too many nutrients into your tank in order to avoid nuisance algae.
Check out the big brain on Pearson!
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