Is there anything else cyano likes?

The red slime remover products are antibiotic based. Since the cyano are a bacterium the red slime will work but the cyano will come back and maybe worse because all you are doing by killing the cyano is basically releasing more nutrients back into the system which will be used by the surviving cyano to re-grow. And you run the risk of killing your biological filter - antibiotics don't care if the bacteria are the 'good guys'.

I would remove the rocks - they are definitely an organic trap and don't provide anything useful to the tank.

You wrote that the cheato doesn't grow much anymore - that is a clue. Your system is low in nitrogen (it can be in the form of nitrate, nitrite, ammonia) so organisms like cheato that cannot fix nitrogen are at a disadvantage because there is not enough nitrogen in the water for them. This basically eliminates the competitors to cyano so now the cyano, which can get nitrogen from the air, can grow on what little phosphate you have in the water.

If you wanted to get rid of the cyano you need to let a little nitrate accumulate in the system - this will jump start the cheato growth and the cyano will now have some competition.

 

Test kits only measure one form of phosphate and that form is only about 2 to 5% of the total phosphorus in the system. Plus many organisms have what is called 'luxury consumption of phosphate' which means they will grab it even if they don't need to use it right now. They basically store it until they need it. So having a 0 phosphate concentration does not really tell you much. Lastly, one way many algae are classified is via their response to phosphate concentration but the concentrations are in the ppb (parts per billion range) or less! And your standard test kits or wands can't accurately measure at these low levels.

Cyanobacteria is a general name to a diverse group of organisms. So just to be sane we have to make generalizations. The important thing to remember is that cyano occupies a niche (ok, really many niches) that compete with algaes and when the ratio of nutrients (chiefly the ratio of nitrogen to phosphate) gets to certain values one can pretty accurately predict whether the system will favor cyano or algae. it is beyond this topic to discuss this further - perhaps another thread. For more on this google David Karl Univ Hawaii and read his about his studies.

The cyano is definitely using the PO4 - the way they out compete is that the system seems to be very low in nitrogen so organisms that need to get their nitrogen from the water can't grow well. But cyano can get its nitrogen from the air so cyano can outcompete everything else. Evidence of this is the statement that his cheato is not growing very well anymore.

C

I agree

I think it all boils down to the nitrogen - where it is and how much. If the water is devoid of nitrogen and has phosphate the cyano 'win'.

Initially carbon dosing may be like striking a match. Cyano are bacteria and bacteria love organics, especially liquid organics that tend to be more easily utilized (this is a generalization but I am trying to keep things simpler). You don't need a lot of phosphate or nitrogen and then add an easy to use carbon and the bacteria are in their sweet spot. I am not sure if I agree that N is typically depleted before P - I thought it was the other way around but when N is low and P is available that will grow cyano because no other organisms can use the P and cyano will get its N from the air - so the cyano has no competition.

This is correct

 

+1

Are you assuming they are relatively small? Certainly agree in that case.

+1, but chumslickhon, do you keep any LPS or SPS corals? How do they look? Are they pale? If the stony corals aren't overly pale that suggests there is sufficient N, for the corals at least. Usually, as long as that's the case, I prefer GFO as P and N have been shown to inhibit stony coral growth. IME GFO is very effective at combating cyano and also should help increase stony coral growth. Whereas, although it has not been shown to be toxic per say, at any level, N can potentially inhibit coral growth through indirect mechanisms...

People add N in the form of amino acids though to make their corals look darker. Amino acids in this usage, are intended to just be a way of adding N without P. This could be useful here too. Also, you can buy KNO3 solution, (such as from here http://live-plants.com/) which may be more easy to measure the N content.

 

very interesting thread. I feel I'm way over my head here. But I have to ask the following:

Is it possible to add N to the water and put the chaeto back to the vantage point? If so, how do u add the Nitrogen?

Sent from my phone using my two opposable digits

 

Ok, that answered it

Sent from my phone using my two opposable digits

 

Magnus, I agree. I'm the one with this problem and am at a loss for what I should do, other than remove rocks from my sump


Here's something else to note.
I usually take a cube of food and mix it with a small amount of tank water. I've read people talking of rinsing your food. How do you rinse food like mysis or cyclopse?

Also, when I clean my sponge I usually rinse with tap water and then ring out dry. I don't see that adding phosphates, but maybe I'm doing that all wrong.

Lastly, I wash my filter socks in the washer machine, rinse cycle only.

Tank is about a year old and never had an issue with cyano before.

 

Some how I missed this post before replying earlier.

I have some LPS and they don't look pale. Hmmm.... Amino Acids, I do have some fuel for reefs, maybe I should start using it?

 

To answer your question about rinsing food. Get a small metal strainer. Put the food in it and run rodi water over it. Then set it in a cup to continue draining. You will be shocked the color of water that sits at the bottom of the cup. Then mix into a cup of tank water and feed with a turkey baster.

 

When I clean my filters I also use tap water. I only make sure they're dry before I put them back. I either air dry them with a hair blower or with a clean towel.

As far as rinsing the food, I use this little mesh device (Don't really know the name for it) that is used to make tea. Here are some pics of mine, it will definitely fit a whole cube, maybe 1.5 cubes.

Here are some pics:

 

Thanks guys. I'll pickup one of those tea strainers. I do doubt that 2 cubes of food a week is doing much, but every little bit will help I'm sure.