Backyard Aquaponics
A place to discuss aquaponics

Hi all, IBC tote system with clay pellets. Have had 50 goldfish for about 2 months, they have been doing fine. Plants are doing well. This week a thin green layer has developed on the fish tank walls and makes the water look dark but it is clear when you take some out. Also several fish have died this week and that has not happened before.

My readings are PH- 6.9 Ammonia - .25-.50 Nitrites - 0 Nitrates - 40-80

My media bed has red wrigglers and I have used a product called Organic Digester right from the beginning.

Is the "algae" harmful? Any suggestions. Glad to find this site and appreciate any help.

Mike

Welcome to the forum Mike, sorry you're having troubles with your fish.

Any information on the water temperature? Are you adding any aeration?

Thank you Scotty. I do have one large aeration stone with separate pump that runs 24/7. Just took the temperature

and it reads 69.8 degrees.

Hi and welcome do you have a photo of the system
At a guess your system is getting too much sun

+1

Seeing what the algae looked like would be good as well

@mbeck5 - Hi and welcome, +1 scotty435 and Food&Fish. Pictures will help. Also keep an eye on your water temp, is the temp fluctuation huge? For example like my system, i do not have a lot of water volume hence my water temp in the afternoon is around 35'C and about 30'C + - a few 'C in the morning and night. It stress out my tilapia and i ended up using marbled goby a much hardier fish but a carnivorous and very slow grower.

Regards

Thanks for all of the responses. I will take some pics today and post them asap. The temperature in Texas right now is between 60 degrees F in the night and 80 degrees F during the day so will post the water them this am and this afternoon. It will be getting warmer soon! No dead fish this morning. I stopped feeding them last night just in case that was the problem. Plants still look great. Appreciate all of your help.

Hi there, tried to add 3 pictures so hope they show up. One is the greenhouse the system is in, one shows the tank and media bed, you can see the tank is dark from the layer of algae, one is a close up of the tank so you might be able to see the algae on the edge from the inside.

The water temp is 68.5 right now, yesterday afternoon it was 68.9. Will keep checking it.

Thanks again for all of the responses. Since the water is still clear with no floating algae, wondering if what is on the tank needs to be addressed and how.

Hi and welcome to the forum.

50 Goldfish are too many fish for that size fish tank and you'll need too cover or paint the tank on all 4 sides to stop your algae, you also have a bit of leaching happening from the timber, I'm not saying that has anything too do with any of your problems but it certainly isn't doing you any favours.

Appreciate the suggestion on the wood. Taking it off asap. I thought the formula was 1 lb of fish for every 5 gallons of water and these are just small feeder fish.

Any thoughts on the algae issue. Checked the water today and again it is clear.

PH - 7.0
Ammonia - .25
Nitrites - 0
Nitrates - looked closer to 80 today.

The basic rule for fish stocking densities is not the volume of water you have but the amount of filtration.

1 fish per 25 litres of wet growbed filtration.

If your growbed was 12" deep it would hold approx. 300 litres = 12 fish

You growbed appears too be slightly smaller than 12" high?

Your algae issue I mentioned above, the problem is the exposed side of your tank.

+1 to all the recommendations above. Love the greenhouse!

Hi Curious,what are you currently growing in your beds ? and how are they with the water temp that high ?

dasboot,

plants are looking great. Purple Beauty, Golden Bell, Sweet Banana, Chiltepin Peppers
Sweet Peas, Italian Basil, Crookneck Yellow and Zucchini Squash, Rosemary,
Thomas Jefferson, Arkansas Traveler, Mortgage Lifter, Patio Tomatoes

This is my first attempt so not sure how they will progress but so far so good. We can expect temps of 90 to
105 degrees F as the summer months come and I have a fan in the greenhouse but may need something else.


joblow,

I am a beginner obviously but don't the size of the fish make a difference as well as the number? and you are correct, my media bed was cut unevenly, so not 12" all around.

@dasboot - I am currently doing mint, ginger and lemon grass. Used to have eggplants, green beans, bok choi and tomatoes. They are growing ok, although bok choi turns out bitter, not sure if it is due to the heat. Just set up a shade cloth last weekend, will see how things go from there.

Regards