Nitrate, phosphate and algae.

[kilnakorr]

Well, no, that would not happen long term in seawater either since the needed trace elements will run out. In reef tanks those come from feeding, dosing, and water changes. The shrimp is not needed, but those trace elements are. Before some limiting trace element run out (such as iron, which already limits phytoplankton in parts of the ocean), algae will run amok, yes.

True. Once a nutrient runs out, so will growth.

Another simple scenario:

I have a thriving planted tank, with no visible algae, dosing all the macro and micro elements. I could stop dosing phosphate and after a while algae would start to be visible.
If I start dosing phosphates again, the algae would dissapear slowly.

 

[kilnakorr]

Don't believe everything you read. People misunderstand that and a lot of things. Again, that's why the chemistry forum exists.

That said, adding pure phosphate can spur algae, including in the ocean in scientific studies (like the one I posted). Since everything else is also in place in many reef tanks (and needs to be for coral growth), elevating phosphate may remove that as a limitation, and algae can be spurred to grow.

But a tank with 1 ppm phosphate vs the much less than 0.02 ppm in the ocean and many reef tanks does not necessarily have algae because something else is limiting it. This is very well understand by people who understand these things.

Check this article:

Skeptical Reefkeeping 9: Test Kits, Chasing Numbers and Phosphate

By Rich Ross and Chris Jury There are many standard parameters in the reefkeeping world that aquarists strive to match in their home reefs – water quality,

reefs.com

Rich’s 150 gallon display, on a 300 gallon system, is running a phosphate level of 1.24 ppm, a level at 24.8 times higher than the often recommended .05 ppm. Photo by Richard Ross.

This is perfect!

Don't believe everything you read

Exactly why I started this thread. When you're new to things, It can be hard to tell what is true, bro science and false.
There's a lot of people who comments, and gives advice based on what they've heard, from a friend, the lfs or their grandfather back in '87 and treat that info as the one and only truth.

I'm simply trying to seperate facts from fiction / half truths.

 

[Randy Holmes-Farley]

True. Once a nutrient runs out, so will growth.

Another simple scenario:

I have a thriving planted tank, with no visible algae, dosing all the macro and micro elements. I could stop dosing phosphate and after a while algae would start to be visible.
If I start dosing phosphates again, the algae would dissapear slowly.

That is presumably by increased competition for something else when the phosphate is added and other organisms grow more..

That exact thing is why, IMO, dinoflagellates become pests in ultra low nutrient reef tanks, but not in higher nutrient tanks, and adding nutrients alone can often help to beat them back.

The same thing does not appear to happen with green algae. Lowering phosphate does not appear to ever spur it, and adding phosphate does not seem to deter it. Adding iron, however, can have that effect, deterring green algae, presumably by spurring other organisms to outcompete it.

 

[beaslbob]

I'm currently fighting an algae outbreak for the last month in my saltwater tank.

I got a new fish 2 months ago, that I started overfeeding because it was rather finicky and wanted to give him more opportunities to eat.

Got a lot more detritus and poop, that started decaying in my refugium because the microfauna couldn't keep up, and made my nitrate/phosphate explode to 5 times the normal values.

Boom, cyanobacteria outbreak, red slime everywhere.

Yeppers and very common. One theory is nitrates dropped down with lingering phosphates. Cyano can get is nitrogen from nitrogen gas hence the cyano bloom. One method of fighting that is to simply kill the lights so the cyano dies off returning nitrates. Then resume with less lighting so the cyano stays away.

 

[beaslbob]

Just wanted to express my interest in this thread during my 3 weeks of inactivity. Nothing preventing me just took a vacation. LOL.

As a suggestion for a test tank take place a partition in a tank 3" from the side with horizontal lighting from outside the tank lighting up that area. Put chaeto or other macro algae in that as an in tank refugium. Fill and start the tank as normal with no filter just at most some circulation.

Wait a week for the macros to expand then acclimate a common cheep male molly. And don't add food for a week. then start feeding a single flake per day. And perhaps add a couple of female mollies to get things going. Adjust lighting to prevent algae except in the refugium area.

Measure nitrates, ph, phosphates, ammonia, nitrites.

Gee wonder what the results would be.

LOL

 

[beaslbob]

oh yea, my interest is based on decades of running fw planted tanks.

 

[Bluecanoe]

What can we use to contain the phosphate problem in Tampa?

 

[Cory]

Lots of iron fertilizer?