Cloudy tank

[sbash]

Hi Everybody!

Several weeks ago, my Low Boy (50 gallon) frag tank suddenly went cloudy. After a day or two some of the corals started to look annoyed and the egg crate started to grow algae.

Another two days of cloudiness and the annoyed corals started to recede. So, I moved the receding corals out and waited another two days. At that point, I could barely see the bottom of the tank (lol, 10" down), so I pulled the rest of the corals and put them into other tanks, no big deal.

I then drained the tank fully, soaked the eggcrate in vinegar to kill off the algea, scrubbed and rinsed it. Scrubbed the few rocks (mainly tonga, super easy to scrub off). Then refilled the tank and kicked it back off to the races.

After a couple days of nice clear water (this is last weekend at this point), I put in a small frag to test the water. It was fine, so I added another, still fine by the next day. Then a couple days later, the water went cloudy again...

I thought it was just a bacterial bloom (it didn't look green like before), and I had just added some plastic that was soaked with vinegar, technically newly cycled water, etc, etc...

By Wednesday it was crazy cloudy again, as in I couldn't see the bottom any more. The two frags (zoas and a toadstool) still looked happy though. When I shut the tank lights off, the cloudiness looked green.

I put in some Seachem Clarity last night, it has decreased the cloudiness a bit, but not as fast as the bottle implies.

Anyone have any thoughts on this odd tank behaviour? Is there any livestock I can add that will eat the micro algae? I hate to drain it, clean it and replace all the rock, but at this point I need the tank to house more frags again...

Thanks!

 

[Hitman]

Sounds like a mini cycle causing a bloom.

 

[sbash]

Sounds like a mini cycle causing a bloom.

That was my first thought, but that doesn't feel right.

Under room lighting, the cloud is greenish. It is also extremely dense, I've never seen a bacterial bloom like this before. I have never seen a bloom this dense or that lasts more than a couple days...

However, if it is a mega mini cycle/super dense bacterial bloom, how long should I wait it out?

 

[Hitman]

That I can’t give a good answer to but I would recommend adding O2 with a air pump or increasing surface agitation some how to put o2 back in the water colum.

 

[Jackony]

Magnesium? Lack of Mg=Ca precipitate. Test for Mg to figure out. If it’s really low, well this happened to me. Ask questions if you have them.

 

[sbash]

That I can’t give a good answer to but I would recommend adding O2 with a air pump or increasing surface agitation some how to put o2 back in the water colum.

There is already lots of surface agitation and an airstone...

Magnesium? Lack of Mg=Ca precipitate. Test for Mg to figure out. If it’s really low, well this happened to me. Ask questions if you have them.

Intersting, it is freshly mixed salt water (Kent's Marine mix), but I tested anyway an the Mg is just over 1500. Which is odd, but the salinity is too high at 1.029 (I just switched to this salt mix, so my mixing technique is off, lol), so I'll fix that right now...

I will note that it is slightly less cloudy today, so either the Clarity is working (just slowly) or the situation is resolving itself. Still, very very odd...

 

[sbash]

Just a quick follow up with this... The tank was still cloudy by the 24th, the density ebbed and flowed a bit. I picked up the Green-Killing Machine (100 gallon model) and it cleared the water up in 48 hours.

I slowly started repopulating the tank, so far just toadstools and zoas, but it is all good.

So yeah, just some fluke giant algae bloom.