Two Similar Tanks, One Cloudy, One Not ?

[alan3513]

I recently set up my 3rd and 4th tanks. One tank is looking perfect but the other is cloudy no matter how many water changes I do. They are virtually the same set ups.The tanks are both Tropiquarium 68(72l), same sand substrate, plants, bogwood, the only difference is a one has a Fluval 2+ and the other a Fluval U3 with a spray bar.
They have virtually the same bio load, get fed the same amount, water changed with a vac once a week (cloudy one more often) , and sit side by side so get the same daylight, and there are no dead fish or rotting plant matter.
I set up the tanks by doing a fishless cycle, firstly by adding the filters that I had seeding in my other tanks, before adding the ammonia and testing as described in the pinned fishless cycle, including an extra week at the end to make sure everything was okay.
The fish were added three weeks ago and seem fine. My stats have remained consistent i.e. P.H.- 6.8, Amm and Nitrite 0 and Nitrate never above 20. Anyone any ideas? ,Cheers, Alan

 

[Curiosity101]

Hmm, the only thing I can possibly think of is trace ammonia being present in the cloudy one. Low enough you can't detect it, but high enough that it's allowing a bacterial bloom to happen.

How long has it been cloudy for?

And how long have the fish been in?

 

[alan3513]

Hi, Thanks for the reply.It became cloudy not long after the fish were added, around three weeks. Have been doing regular large water changes to no avail, fish seem fine though.

 

[Curiosity101]

Whilever no ammonia is registering on the test kit then I'd say just make sure the aeration is nice an high. (The bacteria are areobic so obviously use O2 aswell as the fish). Having said that...I am presuming this is a bacterial bloom, which it might not be.

I'm a bit stumped...
Other than cleaning the gravel some more, and making sure the filter is clean (which it sounds like you're doing), I'm not going to be of much help.

 

[waterdrop]

Traces of ammonia that happen in conjunction with bacterial blooms are a result of the bloom, not a cause of it. The bacterial species involved in the bloom are heterotrophic and are eating some source of organic material and producing the ammonia, which is then being consumed by the autotrophic bacteria in the filter and on other surface objects.

No two tanks and their contents are identical and even slight differences could be enough to set off a bloom in one tank and not another similar one. It could be that some object or material in one of the tanks somehow has either some organic content or is giving off molecules that can be processed as organic. Even the compounds used to seal aquarium glass together can have molecules that will set off a bacterial bloom, just as an example.

Cloudy tanks, however, are notoriously difficult to diagnose over the internet and it could just be some non-bacterial-bloom source, difficult to tell. Sometimes you just have to keep observing things and perhaps something will give you another clue.

~~waterdrop~~

 

[alan3513]

Hi waterdrop, thanks for the reply (sorry for the delay but been away for a few days)Should i start removing some of the items from the tank then do large water changes to see if that make a difference, should i strip the tank down and start again. Was going to replace the internal filter with an external before this problem started but it seems pointless until i sort out this problem, Thanks, Alan.

 

[waterdrop]

Have just seen this but sorry, must run at the moment. Perhaps someone else who's read it can give a more considered opinion... WD