Help, a green 165 gal tank! What are we doing wrong???

**chuckf** · 07-10-2008, 03:50 PM

My kids daycare center has a 165 gal built-in tank. It went green and the fish in it dies about 6 months ago. I volunteered to help fix it up - yikes! Since then it has had :
A complete cleaning with new gravel and decorations
two new Penn-flax Cascade filters put in
50% water changes every 2-4 weeks
An automatic fish feeder added as well as 8-10 African Cichlids
The light timer is only on 4 hours a day; the tank is near a window, but they hung curtains last week.

We have added algicide, a water clarifier and bacteria for the N-cycle
I put some of my filter material from my old tank to help inoculate the filter material with bacteria

It is still a cloudy turbid green! The Nitrate is 5-10 ppm, the nitrite, ammonia, and chlorine are zero, the hardness is 150,alkalinity is 40-80 and the pH is 6.8 to 7.2. What are we doing wrong???

**oldhead** · 07-10-2008, 04:27 PM

Well I'm certainly no expert but I'll chime in and more knowledgeable people will follow I'm sure. But basically your bloom falls into the equation of high excess nutrients in the water + intense light = algae blooms or explosion depending. It was a good idea to the put those curtains in place and I'd keep them closed. Are there fish in the tank currently?? If so you should defnitely look into aerating the water so the possibility of them suffocating is diminished. I'd check phosphate levels and look into some type of remover to go in your filter set up. I have used algone with success in the past although people report mixed results. Water changes may be a good idea on a more frequent basis until the tank begins to clear up. Hopefully some others will chime in here with their thoughts soon. Good luck and I hope everything works out for you!

**Lady Hobbs** · 07-10-2008, 04:29 PM

It's from being near that window. Perhaps now that the window is covered, it will clear up with several water changes. Are those only hang on the back filters? If so, you need a lot more than that for filtering.

**abaigael04** · 07-10-2008, 05:31 PM

phosphate remover (think that's the name - by Odyssea a green filter pad) has worked well for me in the past.... you just cut it to fit in your filter... it is pretty cheap too!

yep, that's the name...

**Dave66** · 07-10-2008, 06:32 PM

Wrote a problem solver guide a month or so ago. Will give you more information about your green water. It's here.

Dave

**jd6405** · 07-11-2008, 02:08 AM

Maybe you should be doing water changes more often then every 2-4 weeks??? Just an idea!

**Sounguru** · 07-11-2008, 03:13 AM

One more suggestion since you have African Cichlids in the tank get that PH up to 7.8-8.2. That will help them out a lot.

**digital3** · 07-11-2008, 05:15 AM

Even though it costs $$$, a UV sterilizer will at least get your water cleared before you get to the root of the problem.

**chuckf** · 07-11-2008, 08:20 PM

Thanks for all the input. I ordered two filters from Odyssea and will statrt weekly water changes. Can I go for 75% changes to speed the process up?

**bushwhacker** · 07-13-2008, 02:42 PM

i had set up my 75 gallon a few months back and it developed a serious green water bloom, i had read about al-gone on this site and others with mixed opinions, well i tried it and it cleared my tank in no more than a week.
cant swear that did it but my tank is clear no i dont do more than 25% water changes every 2 weeks as i have read that algae spore are present in our tap water here