Water Problem in 210gal

[neverless]

I have a problem that for past month i cant get a grip on it

I set up 210 gal tank for my big fishes for past few months i lost control on the watter
Its greenish brown smelly and i cant get a grip on it watter changes wont help at all i am loosing it i have other tanks i use same RO watter no problem i can put new born fry in that RO watter nothing happen no loss there
is this tank still a tank cycling? if it was why so smelly stinks
its a first time i have that expirience when i started the tank i kept it for a month no fish and then checked all so i dont kill the fish i placed a fish in there and all was fine then a month later i loose that watter quality

There are only 12 fish in there not bigger then 12in long and 3 Plecos 12in+

Can you guys give me some ideas watter changes wont help

Filtration 1 FX filter temp set to 77F all levels are noramal proiblem is witht the clearnes of the watter and the smell it kills me!

Thank you!

ps. I will get some pictures soon so maybe you can see

 

[Oreo]

Have you run a full panel of water quality tests yet? If so, what are your results?

I thought algae was typical of high nitrates, and / or too much sunlight. So, my first guess would be to check the nitrates & go crazy with the water changes for a week or so.

This is also where I'd advocate a UV sterilizer. If nothing else, just to get control of the algae problem quickly. Although you'd still want to at least figure out why you've got an algae problem in the first place before depending on the UV as the ultimate solution.

 

[clgkag]

Did you put all 12 fish in at once? Sound like you may have increased your bio-load too quickly and are getting another cycle. There are better experts than me on here, but that's what it sounds like to me. GL

 

[slowef]

lots of carbon.