Cyano reactor?

Wilfried · Oct 6, 2020

My 130 gallon reef has been doing great for over 13 years now. It houses LPS, SPS, some clams, softies 6 different doctor's fish and a plethora of smaller fishes. But my nitrates and phosphates always were a tiny bit on the high side. No big deal. And my corals have OK colours, not the brightest though. But after al this time, I wanted to perfect it. So, I went with an macro algae reactor to help my skimmer out.

I got the pax bellum N18. I filled it up with an initial dose of cheato algae. And four weeks later it was all covered in red cyano algae. (Or maybe it's more brown cyano, if it's cyano at all.) Weird thing is, I have never ever, in those 13 years seen any cyano in my tank. I actually saw it with my own eyes for the first time in the reactor. I played with high flow and a new seed of cheato, same results. Low flow, longer light period, shorter light period. Always the red/brown snot in the reactor killing the chaeto, but never in the display tank.

And the more I read about it online, the more I really really really want the macro algae reactor to work. Not just for the control of organics, but more so for the other benefits.

So guys, what could I be doing wrong here?

Here's my specs:
NO3: 2
PO4: 0.03
DKH: 8.3
CA: 440
MG: 1250
PH: 7.6 (I'm trying to raise this... with the algae reactor. LOL)

Spare time · Oct 6, 2020

I wonder if it is actually dinos since you have practically no nitrate and phosphate

Wilfried · Oct 7, 2020

Spare time said:
I wonder if it is actually dinos since you have practically no nitrate and phosphate

I don't know. It's quite dark brown/reddish, with a snotty texture. Yesterday I cleaned the device, so I'll have to wait before I can actually post pictures of the stuff. But wouldn't dinos spread to the display tank too?

NO3 and PO4 are considered low by today's standards. But when I started the tank, they would have been considered high. I ran zeovit for some time and my corals never looked happier then when my water was 0 on both parameters. But it was just too much work, too much balancing and too much crossing fingers. That's why, instead of going back to zeovit, I now considered an algae reactor as a very low maintenance and safe method to lower the two just a little bit.

Spare time · Oct 7, 2020

Wilfried said:
I don't know. It's quite dark brown/reddish, with a snotty texture. Yesterday I cleaned the device, so I'll have to wait before I can actually post pictures of the stuff. But wouldn't dinos spread to the display tank too?

NO3 and PO4 are considered low by today's standards. But when I started the tank, they would have been considered high. I ran zeovit for some time and my corals never looked happier then when my water was 0 on both parameters. But it was just too much work, too much balancing and too much crossing fingers. That's why, instead of going back to zeovit, I now considered an algae reactor as a very low maintenance and safe method to lower the two just a little bit.

Brown snotty looks like dinos but that is true that it would be weird to only be in the reactor. Its always tricky without pictures but when you post pics I am sure it will get ID'd fast. You could always try the hydrogen peroxide test to see if its cyano or dinos

Super Fly · Oct 7, 2020

I think ur NO3 & PO4 levels are fine, in fact a little low which explains why chaeto wont grow (lack of NO3 to feed it). In my 1st tank I often got cyano in the sump refugium section (low flow w LED grow light) and no cyano in the DT while the chaeto never survived. Also, like some folks I could never grow chaeto in my refugium whereas caulerpa does fantastic.
To help color up the SPS, have you considered using additives instead of trying to lower the NO3?

Buffalou · Dec 24, 2020

I had same issue in my reactor, I increased my lighting time one hour and it now works like a charm. You may have to mess with amount of flow or lighting to get it cleared up. It took me awhile to dial it in. It kept producing, I would pull nasty cheato out rinse off small seed section and run it again. I finally got it were it functions great.

John08007 · Dec 25, 2020

I wonder if it's from your chaeto melting due to low nutrients-nitrate

Dan_P · Dec 25, 2020

Sell your reactor now! This is no time to start experimenting on a system that is doing well.

Dkmoo · Dec 25, 2020

The nitrate might be a bit low - the n18 website does say to does nitrate and typically I've seen chaeti thriving at 5ppm no3.

The other area thats often overlook is a competition issue bc ppl are looking at just the "stats" like nutrient value, growth light par, etc.. and realizing that ur DT is competing with the reactor.

Since the n18 should have sufficient light, I suspect whats happening is that you have a lot more "surface area per volume of water" in your DT than in the reactor. This may especially be common since ur reactor is new and the "seeding chaeto" may be too small and ur tank is very large and established so think about all those surface areas from corals and rock work thats exposed to light and thus impacting NO3 absorption rate. So bc of this competition, the 2PPM no3 you measured is effectively a lot less in the reactor bc ur DT is absorbing them much more efficiently, causing ur chaeto to starve and die.

I did a couple of detailed write ups on another thread trouble shooting fuge failures. Feel free to check it out.

Post in thread 'Refugium failed' https://www.reef2reef.com/threads/refugium-failed.785767/post-8344442

Post in thread 'Refugium failed' https://www.reef2reef.com/threads/refugium-failed.785767/post-8344803