Backyard Aquaponics
A place to discuss aquaponics

So I have a 27 gallon FT and two 10 gallon each media beds with lava rock as the media. This is my first system and I'm trying to cycle it with 6 small 15 cent variety goldfish... Everything was fine for 2 weeks but over the course of a day I lost all the fish. After doing some searching on the forum I believe the ammonia or perhaps something else is too high. The last time I observed the fish a few of them were at the surface sucking for air it appeared. After they were all found dead the FT water has a fishy smell, not cloudy or anything just fishy. I know I need the API test kit and it has indeed arrived today in the store so I will be able to check the system for everything instead of the 4 tests on the strips (ph, hardness, nitrites, nitrates).

My questions are;
1) I have prepared enough water to change out 15 gallons but should I just get the full 27 and change it all out?
2) I have some aquarium starter bacteria, would this help kick start my bio filter?

My thought is just use the 15 gallons as I've given the media beds a few days now to maybe work on whatever is in the water, it smells less fishy. Also, the FT water will be fairly diluted and I will only put in maybe 2-3 goldfish this time. The plants are fairing well so far, I have a few herbs. As for the starter bacteria I'm kind of lost, seems like it might help but then it might be harmful though it says plant and fish safe on the bottle.

So there are a few things. First Welcome to the forum! Next, feeder goldfish are notorious for low survival rates. Third your system is small, and small systems are more challenging. The gasping on the surface can be caused by a number of things, low dissolved oxygen being the most obvious. You may need supplemental aeration. As for the supplemental bacteria, don't waste your money. It won't hurt, but it won't do much either. It is the bacteria that converts nitrites to nitrates that takes a while to grow. Ammonia kills that bacteria, so if you do decide to add it, add it once your ammonia levels are low.

Thanks for the quick reply. I have a T on the pipe heading from my pump up to the grow beds that has a valve and a drilled cap that does my aeration as I didn't think the return of the water from the grow beds created much as for aeration.

So I can switch out the 15 gallons today and add a few fish then test the FT before I add the bacteria since I got it for free might as well give it a shot?

OY! I've been fighting a small system as well. Have probably killed over 100 $0.15 fish.

Where is your system located? Goldfish like cool consistent temp water. Otherwise they get stressed and attack each other.
They don't tolerate high (140ppm or more) nitrates well. They get stressed and attack each other. For me, the above scenarios caused fish to die off a few at a time.

I switched to the $0.15 minnows which tolerate temperature changes better, but don't like it when tank parameters like ph or iron concentrations change radically, With them, I've experienced 2 massive die offs. Currently trying to balance the water to bring in new fish.

Add an air stone and see if that stops the gasping. I always have used and air stone, and never witnessed such behavior.

Mine is on the back deck with a shelf I made that holds the grow beds and leaves the FT in the shade. I'd attach photos but I'm not sure how that works on this forum.

I'm going to pick up a cheap air stone for the FT and helping out gas tap water. I'm going to buy fish now and pick up my API test kit too so I'll see if there is a cheap warmer water alternative to goldfish otherwise I'll raid the change cup in my truck for some more cannon fodder. Thanks for the input and I'll update on what happens next.

So I got a cheap air stone and pump to add some extra aeration and 4 new goldfish as the minnows were not in stock. My ammonia tests 0ppm but my pH is in the high range of about 8.1ish. I added the free aquarium bacteria I had on hand as well. Everything seems to be doing well and the fish are happy looking exploring their new large FT. I'll test for nitrates/nitrites this evening when I get done with some other things...

Are you still cycling?
If so... try fishless cycling.
If not.. I feel sorry for your fish

With my first AP system I'm also doing comet gold fish, about 32 now in a 100 gal FT. I was learning EVERYTHING AP-related, so I cycled fishless for 3.5 weeks until I got the ammonia, nitrites, and nitrates moving in the right direction. I kept in touch with a dedicated tropical fish store in the area, which gave me good advice at times. I did started with some microbe bacteria to jump start the system. It stank like rotten eggs, but it seemed to do the trick.

I also ensured my pH level matched that of the store's tanks when I introduced the fish. These fish were also maintained entirely outside the store in the Georgia weather. They had been outside at the store for a few weeks, so they were used to outdoor conditions by the time I introduced them to my outdoor AP setup.

Knock on wood, I've not screwed up yet (too much), so I've not lost any fish. But Georgia winter (mild I know) is coming, so we'll see how that treats them.

I feel sorry for my fish too, but the pet store guy assures me they live longer with me than with most of his customers. These are feeder fish after all.

Anyway, I've been fully cycled for 8 months already. First batch of fish survived that, but I keep having other issues I'm learning through. I will only add fish now when the system appears stable and the numbers look right. Doesn't mean there won't be another "hiccup".

Whats your total growbed media volume?

30 gal or 113L FT is is roughly the same.

BTW the 100 fish was not all at once. Max I had at one time was 25, added to the system in 3 batches.