macroalgae vs cyanobacteria

[Kelmen]

Well, many of reefers setup macroalgae in refugium to reduce the cyanobacteria. So do I.

But now the cyanobacteria is getting a feethold with my macroalgae (Caulerpa Racemosa) in my refugium.
Also got some Halimeda too.
:mad:

I do have some cyanobacteria in main tank, but I'm holding them off now.

What's your advises so that I can help the macroalgae win this battle?

[bluenassarius]

water current.

[pledosophy]

1. Lower refugium tank temperature

Lower temps will slow the growth rate of the bacteria.

2. Less Photoperiod
If the cyano is removed from light it cannot grow.
Normally after 48 hours with no light the cyano will die

3. If your lights are more than 6 months old it may be time to change them.

As lights age the spectrum of the bulbs shift to favor nusiance algae growth.

4. Add Oxygen to the system

Increased amounts of oxygen are harmful to the bacteria.


5. Chemical treatments.

Many aquarists have had great succsess chemically with a product called chemclean. It is a white powder that is added to the water. All filters are turned off and as many airstones as you can add are added to the water. 24 hours later a 20% WC is required. This will usually fix the symptom.

Cyano and hair algae feed off excessive nutrients in your system. The best way to stop reoccurance is to solve the problem which is phosphates, or over feeding of the tank. I have battled cyano a few times and now rely on chemical treatments when needed.

Good Luck to you.

[Kelmen]

Me don't have chiller setup, yet.
The temp at the refugium is generally 29 - 30 degree Celcius.

The photoperiod is 12 hours of 36W PL. Its new, just replaced. I probably will looking for new replacement, as nearby compartments start to have these nuisance cyano growing :(

I started to reduce the sump water level, as the lower water level agitated the surface much. Also put in a surface skimmer work when light is on. And pour the water back into the protein skimmer compartment.
The water surface is far more cleaning now.

But probably due to the sump is within the cabinet, an more enclosed environment, the air quality may be poor. Will look into better air ventilation.

I'm very reluctant to adopt chemical approach.
Anyway I stocked in 2 new snails and 1 sea cuke, to help some cleaning there.

Thanks for the feedback, have to tinkering by self now. :)

[kmk2307]

Do you use RO/DI or another type of purified water to mix your sw and topoff? Do you test your phosphates? My advice would be to use a product like phosban or rowaphos to remove some phosphate. If lots of phosphate is present in an otherwise normal aquarium with at least moderate lighting, cyanobacteria can well. Do you test your nitrates? If you have zero detectable nitrate then your caulerpa may be starving. Cyanobacteria can fix their own nitrogen, caulerpa and all other eukaryotic algae cannot do this. I don't believe lowering your aquarium temperature will help the caulerpa get an edge over the cyano.

HTH,
Kevin

[Kelmen]

I run parameters chk about monthly, but generally after water change. But then my water change is quite low, about 10 liters for 340 liters.

Most parameters are good, except the pH.
I can say all parameters (ammonia, nitrite, phosphate) are near undetectable level, unless my testkits screwed up.
Nitrate is all the while under 0.3 ppm (nearing the lowest level of my testkit)

The phosphate testkit is brand Prodac, an Italic stuff, I doesn't put much faith into it.
Other testkits are from a set, AquaPharm, US stuff, should be good enough.

the max of pH testkit is 8.8, which my result is past 2 months been giving me the max! (well, I mayhave some problem coloring recognizing, who know)
I have stop running kalk dripping, now only buffer up the KH once awhile.

I'm using filtered water (can be straight for human drinking). I did run a test on the water, PO4 also undetectable.

I have lighting problem month ago, now the caulerpa seems growing good again.

Again, checimal approach will be my last resort. But thanks for the tips anyway :)

[Samala]

Interesting.. why do you think your pH is so high? I get high pH's like that with my very photosynthetically active tanks because the plants are pulling the carbon dioxide out of the water... aeration helps bring it back down to normal levels.

I ask because when the pH creeps up in my tank, I get diatom outbursts.

>Sarah

[Kelmen]

Oh, good point. It can be a lead.

I dunno. I even tested my new salt water, also high pH. I'm using Instant Ocean.

Guess I may tackle at this one. :)