Green Cloudy Water and UV Sterilizer

[steamman]

I have recently getting back in the hobby. Should I shoot myself now LOL? I have around thirty years experience in salt water reef tanks. I really had a good start cycling my 150 gallon tank. No algae blooms, no cyano, no diatoms since I started the tank. I really took my time and let the tank cycle in the dark without fish.

[IMG][/IMG]

It looks blue higher in the water column because the back is painted blue.

At around 4 months the tank went cloudy green. I don't think it is green from the lights. I run a hybrid light system with with a 61" Aquatic Life and Orbit Pro LED duel 72" fixtures. I know it is a mix match in sizing but it works.

Today I installed a Vecton 600 UV sterilizer. I wanted to post the tank pictures before and after. So here is the before running the sterilizer picture. I will updater tomorrow.

I have a very small bio load in the tank right now. A tailspot blenny, 1 firefish, 3 Lyretail Anthias, 3 Bangaii Cardinal Fish, 1 Purple Tang, 1 Yellow Tang, a pair of skunk shrimp, 12 small blue hermits and a dozen or so snails.

About a month ago I went to Reefapalooza in NJ. I added some LPS ans SPS frags. At that time I also added some pods and live algae.

I do 20 percent water changes every week. I dose with NOPOX but I only add three mil a day since the cloudy water started a couple weeks ago. I have undetectable nitrate and phosphate.

I run a large old Deltec II skimmer. At least I think that is what it is. It has two 2600lph Eheim pumps on it. My turnover with two DC pumps is around 2500 to 3000 gph. I also have two powerheads in the tank just to create counter currents.

[bblumberg]

Green algae cannot grow without phosphate so I question whether you really have zero phosphate. I'd try a new test kit. It is possible that the algae themselves are using the phosphate, but that implies that there is a constant source, else they would die out. If you know someone with a microscope, it might be worthwhile checking whether you have green algae (largish cells with nuclei) or cyanobacteria (blue-green algae), much smaller and no nuclei. Cyano can survive low nutrient levels, green algae not so much

I expect that your sterilizer will help, but you may just transfer the problem from floating algae to GHA, bryopsis or some other algal pest...

[steamman]

Originally Posted by bblumberg

Green algae cannot grow without phosphate so I question whether you really have zero phosphate. I'd try a new test kit. It is possible that the algae themselves are using the phosphate, but that implies that there is a constant source, else they would die out. If you know someone with a microscope, it might be worthwhile checking whether you have green algae (largish cells with nuclei) or cyanobacteria (blue-green algae), much smaller and no nuclei. Cyano can survive low nutrient levels, green algae not so much

I expect that your sterilizer will help, but you may just transfer the problem from floating algae to GHA, bryopsis or some other algal pest...

Thank you for your input. I did not say 0. I said undetectable. I use the Hanna phosphate meter. Last test showed 0.0. The accuracy at that level I believe is + or - .04.

I never thought Cyano was free floating. Interesting avenue to pursue.

Myself and a friend of mine thought it may be that the live phyto I put in the tank may have started a culture in the tank.


I will take pictures after 24 hrs and post them to see if there is improvement.

Thank you for your interesting theories and advice.

[bblumberg]

0.04 is probably not going to cause an algal bloom. I don't know for certain whether or not cyano can grow suspended, but expect that they can. In either case, without a constant source of nutrients, the bloom would use up what is available and then be gone. Live phyto could have certainly been the trigger to start the bloom, but what is sustaining it?

I had a brief, but similar problem a few years back. We had a department retreat at the Ocean Institute in Dana Point and collected some plankton out in the bay with a plankton net. Rather than dump the remainder back in the ocean afterward, I brought it home and put in my nano, thinking it would be decent fish/coral food. There was a mini algae bloom that lasted about a week as well as a few new critters that lasted for a while.

[bblumberg]

ps. where in NJ are you? I grew up in Voorhees until moving to CA in the last 1970s.

[steamman]

I feed heavy. I don't know if it would be heavy enough to sustain a phyto culture or not. I used to rotifers but on a frozen phyto diet. I have done a lot of research on culturing live phyto. They need nitrates for fertilizer to thrive. Now whether they can survive the amount of water flow in my system or the large skimmer I don't know.

It's really only in the last week that I am getting the ultra low nitrate and phosphate readings. Maybe if I wait it out it may cycle itself out and disappear. Maybe it won't because of how much I feed the tank.

I am in the Woodbridge area.

[steamman]

Duplicate

[steamman]

The Ultra Violet light worked like a charm. Here is what the tank looks like after 22 hrs.

Not 100 percent clear yet. I will give it another day for that.


[IMG][/IMG]

This is what the skimmate looked like. Looks just like a phytoplankton culture mixed with a bit of regular old brown skimmate.





I expect that this was a phytoplankton culture. That could also explain the ultra low nutrient levels I was getting. The algae was consuming everything. Wow could you imagine if the algae did not get the water that cloudy what a wonderful thing that would be for nutrient removal?

[steamman]

I should have posted this picture from the side of the tank yesterday. I really gives you a better view of what the water really looked like without the blue background.



I ordered a microscope today. I will get it by Sept. 11th. I will freeze a sample so I can determine if this was truly algae or if it was something else. It is a microscope with a camera so I can post pictures. I am not sure if I will be able to identify the organism myself.

[steamman]

I decided to take the UV sterilizer off line earlier today. I do not want to kill off the algae culture if that indeed is what it is. I may be on to something here. Maybe a better way to cycle your tank and avoid the normal hair algae and other nuisance outbreaks. I may try to replicate what I have done to see if it is viable. This type of algae is definitely easier to deal with than the other typical new tank syndrome algae.

[steamman]

I have no idea why the link stopped working for the after 22 hrs photo.

[steamman]

Even though I turned off the UV sterilizer after 28 hrs the water continued to clear up.