Can't get rid of cloudy water

[Nardinim]

Hi all,
started my first marine nanoreef last february.
It's an 8g tank setted up for soft and lps with about 12lb of live rocks .
I use a natural method for maintenance changing 10% every week.
The light is a Nemolight 18watt and the water I use for changes Is produced on my own with a five stages osmosis: I measure 0 tds in the out.
The pump for the flow is a sicce 2000 (started with a Hydor Nano Koralia 900 and then moved up trying to move more the surface"¦)
No fishes inside, no food for corals: the only thing I add once a week is water for changes with Kent salt.
Values are:
Ca-400
Kh-9
MG:1280
Salinity :35
Phospates, Nitrates, Nitrites: 0
Actually the tank is populated with: Xenia, candy cane coral, torch coral, few zoanthus, Duncan coral, green star polyp and an Astrea slug
That said here is the problem: starting from 2 months ago I noticed dirty on the glasses that once cleaned came back after few hours and, day after day, the water became cloudy like fog.
This happened three times now and the only method I found to clear water was using an UV Sterilizer
Every time It happens corals are not affected by this: they are open and It seems to me they are not suffering.
Tried lot of actions:
"¢ Added carbon filter
"¢ Added anti nitrates and phosphates resin
"¢ Tried to move more the surface with the 2000 liters pump instead using the 900 liters pump
"¢ Lowered the light period (at this moment I have 10 hours of light)
"¢ Added Seachem Clarity
"¢ Added a mechanical filtration with Sera Crystal Clear changing it daily

If I don't use UV the cloudyness lasts forever: at this time is about one month I've got It for the third time and I'm waiting your suggestion before putting another time the UV Sterilizer inside.
Do you have an idea of what's happening?
If you need further informations please ask.
Thanks in advance,
Marco

Clean
https://ibb.co/dRa0GR

Cloudy
https://ibb.co/ePcxwR

 

[Coralfuture]

That sir is a mess of bacteria and will not be removed EASILY with what you are doing. I would suggest a protein skimmer of some sort even a DIY one would do with that much bacteria. The UV sterilizer is a bandaid unless its on all the time. Either way good luck with this.

 

[Nardinim]

That sir is a mess of bacteria and will not be removed EASILY with what you are doing. I would suggest a protein skimmer of some sort even a DIY one would do with that much bacteria. The UV sterilizer is a bandaid unless its on all the time. Either way good luck with this.

Thanks for your replay but I'm wondering what are all those bacteria eating?
With no food in the tank they shouldn't be there so long.
Am I missing something?

 

[outy]

With no food in the tank

Light is a food, we are talking chemistry here.

Even slight traces of coral waste can be food.

 

[outy]

/// natural method for maintenance//// obviously not working. poor lighting is also suspect.

.its such a small place parameters will jump all over the board, but being so small there is not a lot of space for beneficial bacteria.


I would do a 100% water change and see how long before condition returns if you must run a bare bones set up.

Whats PH?

 

[outy]

If I don't use UV

Never used UV in over 25 years of doing this. .

Its a combination of poor lights, not enough good bacteria, new tank syndrome to some point here.

Without feeding you have delayed the breaking in process. is a good guess.

I would use at minimum 3w leds for any coral. Those 1 w leds are to small imho

Almost to clean of a tank

 

[JTL]

Like has been said, that is a very small volume. The live rock is working based on your params. I am a big believer in running carbon all of the time but you need to get good flow through it. Do a large water change and then do 25% per week. With no skimmer to help with removing organics you only have filter media and water changes. I am in the process of cycling a 20 gallon for a q/t and have never had a tank this small either so I am not the expert.

 

[RobSpeed13]

i never understand how tanks get cloudy. never has happened to me, but wow i must say your clear photo and cloudy photo are crazy. personally i keep things simple though. so makes me wonder if all the extra carbon, resin, stuff helps or makes it worse?

 

[JTL]

i never understand how tanks get cloudy. never has happened to me, but wow i must say your clear photo and cloudy photo are crazy. personally i keep things simple though. so makes me wonder if all the extra carbon, resin, stuff helps or makes it worse?

You are lucky or practice better husbandry. Most of the cloudiness is undissolved organics unless he is adding supplements which I don't think is the case. The amount of junk my skimmer removes is amazing and I don't over feed.

 

[naimasreef]

if you can find a skimmer you like . . . will likely help out a lot.

 

[drysea]

skimmer. I guess you could get sponges but that has its own issues

 

[pisanoal]

Am I the only one that sees no need for a skimmer on a coral only tank? Its not like this is a 2 gallon Pico tank. Its the size of a small biocube. Should be perfectly fine running with no skimmer ESPECIALLY with no fish and very little food input. There are plenty of smallish tanks running sunless/skimmerless WITH fish.

OP, What salt are you using? Some contain organic matter. How did you cycle your tank? Did you start dry rock? Ive seen some issues with dry rock and bottled bacteria. My theory is the type that is used in some brands is prone to having a monoculture situation where one type gets a major foothold amd out competes. I had a similar issue. I would try to get a couple different kinds of bottled bacteria additives like Seachem Stability. Dose it as directed over several weeks. Run the uv when you aren't dosing, clean the sand bed often if you have one, and do weekly 20% or more water changes until new strains can take hold in your substrate.

Not saying this is definitely a fix, but I'd be trying that way before considering a skimmer. Unless you already had one to throw on the tank to help out for a while, I'd say its way overkill.

 

[pisanoal]

Also, how are your corals doing? I would look at them before taking any suggestions on lighting to heart. Ubkess they are dying off and adding organics to your water, this is not a lighting issue.

 

[Nardinim]

OP, What salt are you using? Some contain organic matter. How did you cycle your tank? Did you start dry rock?

From the beginning until now I used Kent Reef Salt Mix.
I started the tank with live rocks and full light on february and waited for the algae cycle without any change for about 3 months.
I added my first soft (xenia) at the end of may after checked perfect values for Ph and No3.
All went fine, with few more corals added, until the beginning of August when the fog appeared.

During the all period, until now, no one coral died.

 

[reefnoob88]

Empty some water into a white bucket and check to see if its green or white? If its green you could have a micro algea bloom in the water column? I had the exact same symptoms and my local fish store told me to do the above to narrow down either a bacteria bloom or micro algea bloom. Mine happened to be micro algea bloom just thought it worth mentioning hopefully you can narrow it down.

 

[Nardinim]

Empty some water into a white bucket and check to see if its green or white? If its green you could have a micro algea bloom in the water column? I had the exact same symptoms and my local fish store told me to do the above to narrow down either a bacteria bloom or micro algea bloom. Mine happened to be micro algea bloom just thought it worth mentioning hopefully you can narrow it down.

Just did the test: It's a white bacteria bloom.