My water stays brown and stinky. I need help!

[Justin Miles]

I have a 75 gallon tank and am growing 27 tilapia indoors. My water stays horrible and I don't know what is wrong or what to do. I'd be very appreciative if someone could walk me through the process.

[Keith Rowan]

what are you using for filtration?  you're definitley overstocked and underfiltered..

reduce population, or add growbeds

[Randy]

More info on your set-up would be helpful. But I will take a shot in the dark based on my experience with 20 Tilapia in a 125 gal aquarium. I had brown water that closely matched the color of the feed I was using. I cleared up most of it by switching feed. As for stinky water you probably have a build up of solids. If you have a bare bottom it should be apparent, but if you have gravel the solids will find their way down into the sub-straight. I got tired of cleaning my gravel and took it out. Without the gravel trapping the solids the problem moved to my filters which I was having to clean every other day. To get relief from that regiment I reduced the amount I was feeding them. I have constructed a new filter out of a 30 gal trash can and two 5 gal buckets and will add that to my system after I complete work on an Over Flow System. Hopes this helps.

[Justin Miles]

Thank you both for your responses. I'm pretty much a neophyte but what I can share is that I have a flood and drain system and only recently started using a filter to clean up the murky water. I don't know if or how I should be using a bio filter. I've read that if I use a filter (the one I'm using now is for fish tanks, 20-30 gallons which I know is too small) them it will also reduce the amount of nitrates in the water and the plants want get the nutrients they need. I have a bare bottom and I thought that that might be the problem; left over food. What I think is doing it is a build up of solids in the grow bed itself. There are a couple of brown pools of gunk right outside where the water floods the bed. Sometimes I wash the rocks off but that doesn't prevent it from returning. I've reduced the feeding which seems to work after I change the water, but not for long.

[John Cubit]

You are over stocked.  You really need to have a minimum of a 75 gallon growbed provided you go by the 1lb of fish per every 10 gallons of water ( I think that is the base).  And that is not the current size of the fish but what they potentially can grow to is what you need to consider.  If you are going to have more fish that that you might get away with 150 gallon grow bed.

Water will be discolored to a point but when you get a smell from the fish tank something is wrong.  What are your chem readings for pH, Ammonia, Nitrite and Nitrates?

You may want to add a swirl filter on your current setup to help get solids out.  An aquarium filter really is not going to help you at all.  I can trick my grow bed in to suck settled solids out by waiting till it is close to the bottom of a drain cycle and then increasing the water flow in so that the siphon stays on.  I have only done that twice until I added worms to the grow bed and they really are doing an excellent job on cleaning things up.

Get us some more details on your setup.

Here is a link for a swirl filter design from Backyard AP

http://www.backyardaquaponics.com/forum/viewtopic.php?f=8&t=6419

There are many designs to setup a system, but you should always start with a 1:1 ration for tank to bed.  Keep fish at a minimum (1lb to 10 gallons of water).  FT feeds Grow bed, GB fills FT with clean water.  That is the simplest to explain and the whole thing explodes in many variation on the theme.  Grow bed is your bio filter.  What happens after that is really up to you and many many things can be added.

[Randy]

I have made a filter by putting holes in a cool whip container. Fill it with "poly-fill" from Walmart (near the bed pillows) and use it to pre-filter the water going into the GB. A flood and drain GB is a pretty good bio-filter. Your aquarium filters will not reduce the amount of nitrates available to the plants as long as they are part of the closed system.

[Alex Veidel]

Are you using hydroton for your grow media (or a hydroton substitute)? If so, did you wash it before using it? Bags of hydroton have a lot of red silt that should be washed away before use in your system, otherwise it will turn your water brown. How big are your tilapia? Are they just fingerlings, or are they more on the adult side? You typically wanna shoot for 5-10 gallons of water per 1 lb. of fish. As for the smell, how much are you feeding them? Does a lot of feed end up uneaten on the bottom of the tank? Also, check around for dead fish, they tend to smell bad too. I agree, do a water test and let us know what the ph, ammonia, and nitrate levels are. Oh, and how are you aerating your tank? Do your fish look like they're gasping for air in your tank?