I don’t understand ugly stages

[Miami Reef]

New tank with a mix of dry and live rocks. The live rocks don’t develop algae while the dry rocks develop diatoms.

I’ve been reading a few posts about people saying to remove all rock bonded phosphates with lanthanum chloride/GFO etc.

But it just doesn’t work, and if it did, you’d just get Dinos instead which is way worse.

Phosphates around 0.10ppm.

Very infuriating because there’s no clear cut answer. What organism takes rock territory? Bacteria or photosynthetic organisms?

If you aged a live rock in complete darkness and then shined a ton of light, would algae grow, or will it be limited due to a lack of space on the rock?

I have an acrylic frag rack that has diatoms too, and I can assure you it’s not leaching phosphates, but older tanks don’t grow algae on their frag racks, or do they?


What is changing in mature tanks?

FYI I don’t hate algae, I just want to understand the process of why algae isn’t common in older tanks. What’s changing in those older systems that seem to have the same trace elements, nutrient levels, and lighting as new tanks.

 

[Miami Reef]

Here’s a 12 minute video from tidal gardens:

They started a 2,000gal tank with dry rock. This tank is connected to thousands and thousands of gallons of other tanks in the show room.

Only the 2,000 gallon tank had the algae. I would expect the phosphates to reach equilibrium with the total water and fuel algae in all the tanks, but it did not happen. Actually, the 2,000 gal tank tested 0 phosphates which we can assume the algae is directly consuming the nutrients as it gets leached out.

Than also noted how algae would bloom in an area where the dry rock crumbled in dust form. He inferred that the rock was directly fueling the algae.

Nathan, a custom of tidal gardens, purchased the same exact dry rock and did not have nearly as bad of an ugly stage. He had a lot of tangs and herbivores. I don’t know if he ran any reactors, but I highly doubt he could strip his nutrients from the rocks before the algae could get to it first.


This is what I’m concluding, you cannot prevent an ugly stage by reducing nutrients if you have your lights on, since algae will most likely get to it first and starve the tank to 0.

Herbivores are key to managing the ugly stage.

 

[chris k.]

I do not have any info to back my hypothesis. Just my experience and observation, as tanks and rock and anything in the tank matures. A thin film develops on the surfaces preventing algae from growing. If you look at the above situation when the rock crumbled to dust it lost that surface film. Again just my observation.