Coralline? Cyano? Something else?

r33fermaddness · Feb 19, 2021

Hey all, lookin for some more experienced opinions on what I’ve got growin on my rocks, this is my first tank and I’m not quite sure what I’m lookin at.
My gut says cyano, due to high nutrients, but people have told me my tank’s still a bit young. I want it to be coralline but I again think the tank is too young.

Tank is a 90g FOWLR just around 3 months, started running around the end of November/beginning of December of last year. Nitrates have been hovering around 10ppm for the last month or so, phosphate is around 1ppm. Using Red Sea’s nitrate test and API phosphate test.
I’m running GFO in a reactor to try and lower the phosphate, haven’t seen much of an effect, it’s been measuring around .5-1ppm pretty much since I started the tank.
I target feed Hikari Marine S Pellets and frozen Mysis shrimp (my banggai Cardinal won’t eat the pellets) twice a day, only starting the Mysis about a week ago when I got the Cardinal.
About a month into running the tank I added the small coralline encrusted rock you see in the second picture from my LFS, as well as a bottle of ARC Reef’s purple helix.

For the last month or so I’ve seen the faded red spots start showing up and growing slowly on the rocks, the first picture is probably the most concentrated patch, with the white spot showing up only a week or so ago. Nothing but diatom buildup on the sand and glass which I clean weekly during a 10% water change.

So, thoughts? If this is cyano, any suggestions on how to avoid it?
Thanks for your time!

Idoc · Feb 19, 2021

The scattered pink spots actually do look like coralline algae starting!

The other brown on the rocks looks like normal diatoms.

The darker red in the first picture does look like possible cyano starting, which makes sense with the huge No3/Po4 disparity. But, that is on the top of a rock where you would think that the flow would be pretty strong...and cyano doesn't normally like a lot of flow. This could also be coralline starting...if it starts to form "sheets", then it is definitely cyano.

So, at this point....I would not recommend doing anything drastic since the tank needs to go through some of these crazy algae swings on its way to maturity. Be careful with GFO...only run it partial strength to slowly bring down the Po4 to around 0.05-0.1ppm and attempt to maintain those levels. Maintain around 5-10ppm for No3...manage this with water changes.

attiland · Feb 19, 2021

Your tank is new those stains could be cyano/Dino/diatoms. Without microscope it is just a guess. Wait do nothing for the time being. Diatoms would normally disappear within 2 -3 weeks. If cyano it will grow thicker than now and will turn more likely more purple. Dinos will stick for longer but need to be IDd by microscope before any treatment.

Buffalou · Feb 19, 2021

I agree with ldoc, don't do anything drastic, patience and let the tank grow through the early stages. I wouldn't use the GFO at this early junction. I'm more a believer in adjusting things naturally. Are you at the point that you have introduced a clean up crew to the tank yet? I would think if not it would be the next progression going forward if you haven't yet.

r33fermaddness · Feb 19, 2021

Buffalou said:
I agree with ldoc, don't do anything drastic, patience and let the tank grow through the early stages. I wouldn't use the GFO at this early junction. I'm more a believer in adjusting things naturally. Are you at the point that you have introduced a clean up crew to the tank yet? I would think if not it would be the next progression going forward if you haven't yet.

I’ll probably take the GFO offline this weekend then, it doesn’t seem to have done anything running for about 2 months now. I did add a small cleanup crew before the fish, 5 turbo and 5 nassarius snails. I lost the turbos all last month, I’m thinking they didn’t have enough food or the temp was too high for them (from what I’ve gathered from other’s experiences with them). The nassarius snails are doing great, and I added a tiger conch snail a few weeks ago, also doing great. Do you have any suggestions as far as other cleanup crew members that would be beneficial at this point?

attiland · Feb 19, 2021

r33fermaddness said:
I’ll probably take the GFO offline this weekend then, it doesn’t seem to have done anything running for about 2 months now. I did add a small cleanup crew before the fish, 5 turbo and 5 nassarius snails. I lost the turbos all last month, I’m thinking they didn’t have enough food or the temp was too high for them (from what I’ve gathered from other’s experiences with them). The nassarius snails are doing great, and I added a tiger conch snail a few weeks ago, also doing great. Do you have any suggestions as far as other cleanup crew members that would be beneficial at this point?

Turbos don’t like new aquarium to my experience. Almost nothing to eat and often swings of water parameters takes them out.
Hermits in the other hand more hardcore can survive much more.
Pods can do excellent cleanup but might be too early for that yet.