Macro algae dying in reactor

[Tradevg]

Hey all. I setup a macro algae reactor about 6 weeks ago for my 12 gallon FOWLR tank. It's my first saltwater tank I was given about 2 years ago and so far been using it to learn more about the hobby before getting a larger one and diving into corals. Occupants include 1 clown, 1 orchid dottyback, yellow watchman/pistol pair, tuxedo urchin and a few hermits and snails.

First 4 weeks things went as expected - during which I had two clean outs with good growth and reduced nutrient count. Today (3rd cleanup) I found a slimy mess in the reactor. Only thing I have done different is I introduced amphipods and the urchin after the last reactor clean out ~2 weeks ago, both ordered from Algaebarn. Light schedules are also unchanged. I run my reactor lights opposite to the DT lights. I haven't done any water changes in 5 months.. only replaced small water losses during reactor clean outs. My phosphates are ~10ppm and nitrates are zero (API tests - I know get a better brand test). Phosphates went up a little as they were zero 2 weeks ago. Salinity right at 1.024 based on my refractometer.

I can only think of 2 reasons for the slime: nutrients too low (unlikely since I continue to see a little GHA in the tank) or somehow the pods screwed things up.

Any thoughts would be great. Thank you!

 

[saltyfilmfolks]

The lights may be too bright. Or the flow to low.

 

[Mr.Rocc]

The lights may be too bright. Or the flow to low.

I was thinking the flow as well!

 

[Tradevg]

Thanks guys for the quick response. I had turned the flow down a smidge after adding the pods, but just for a few days to let them get settled. I had added them directly into the reactor. Didn't think that'd make such a difference. Turned up the flow already. Is it more the better in your experience?

Hopefully the remaining chaeto stock isn't too far gone to recover.

 

[saltyfilmfolks]

You'll want to add bugs to the DT. They'll make their way around the tank from there.

And yea. Just like corals and terrestrial plans. They do need good flow.

 

[Tradevg]

Thx Salty. Will post an update in a week.

 

[bif24701]

Not changing water means you are not replacing some elements the algae needs to grow other than PO4 and NO3. Do some water chAnges should help

 

[Tradevg]

I'm not an expert or as experienced as you guys so did a 15% change. The point of the algae was to reduce water changes and seems many people have been able successfully do so. What other elements does chaeto consume?

 

[saltyfilmfolks]

Iron is one.

It might be worth a shot.
I'm not a big fan of the never doing water changes thing. Fwiw.

 

[bif24701]

I'm not an expert or as experienced as you guys so did a 15% change. The point of the algae was to reduce water changes and seems many people have been able successfully do so. What other elements does chaeto consume?

Reduce, not eliminate. Unless you are able to replace whatever the algae needs.

Also could be a flow problem through the reactor.

 

[Tradevg]

Ha.. forgot I also was running purigen in my canister which I removed when I cleaned it during the water change. Perhaps it is a lack of nutrients since the algae had good growth for the first month.

 

[SantaMonica]

Algae consume ammonia/ammonium, nitrite, nitrate, phosphate, CO2 from their air, and alk from the alk, and metals.

Probably not too bright though... those strip lights are very weak.

 

[Tradevg]

But if that was the case, why would the chaeto grow like crazy for 4 weeks under same lights. Gonna try feeding a little more but afraid my stock is too far gone. Its all clumped up at the top of the reactor.

 

[SantaMonica]

Sometimes algae based filters do this. Just keep it slime out, and green it, and see if it picks back up.

 

[Tradevg]

Update: tried water changes, checked flow, put in fresh batch of chaeto. Within a month the algae was dying. Didn’t get a single cleanup - no growth. I think the theory is sound but for some reason not working for me. So I am giving up algae reactors. Ughh.

 

[DropInTheOcean Matthew]

Tradevg.. I’ve been having the same issue with mine. Chaeto growing in sumo but not in reactor.. I tried turning down the lights, hope it works!

Good luck!

 

[DropInTheOcean Matthew]

And I was having my lights on 24/7... don’t know if that’s what’s preventing growth...

 

[SantaMonica]

When in doubt, just use 18 hours of light.

 

[DropInTheOcean Matthew]

When in doubt, just use 18 hours of light.

Thank you, Monica! It’s growing slowly but surely! Nitrates spiked a bit so I put some chaeto back in the sump under high powered grow lights. Reactor is still going