Backyard Aquaponics
A place to discuss aquaponics

Hi Guys. I read about Aquaponics a month or so ago and thought it was too interesting not to try. I'm on the Yucatan peninsula in Mexico (think >110 + 100% humidity) and wanted to see how it'd work here.

The system is built from a giant "bucket" i found in centro. I assume it's supposed to be used for washing or something. I also used an under-bed storage box from costco, which I've since realised might be slightly shallow, some piping we had around the house and some hydroton i ordered at painfully great expense on Mercado Libre (Mexican eBay). The fish are simple goldfish, small carp and one of those sucker fish I bought at a small sunday market.

It took me a couple of weeks to get the siphon to work realiably, but now it's working fine.



Originally I was thinking of putting the storage box's lid on with holes cut for the cups, but no one else seems to do that, so I'm not sure if it's a good idea. It would certainly make removing the lid impossible once the plants were established.

I'm planning to build a frame to put the grow bed on with some thin plywood to keep the sun off the clear plastic sides. I cover the fish during the day because the sun here is very, very strong. The whole thing is under plastic shade mesh, but it's still really strong.



At the moment the system doesn't have a sump, so the fish's water level drops a few inches when the grow bed is full, but there still seems to be plenty for the 7 fish we have.

It's been running for about 2 weeks, but the plants seem still in stasis. The cucumber's twin planted at the same time now has 2 huge leaves and a third on the way. I bought some seaweed extract and dropped in a few ml to try to give the plants some food before the bacteria kick in, but I'm not really sure how much I should use, and how much is safe.

I've also bought some EDDHA chelate, but I'm assuming that's not worth using until the bacteria kick in and the plants actually start growing?

Welcome to the forum

What kind of food are you feeding to your fish? This can also affect the growth rate of the plants. Your typical flake food for goldfish probably isn't going to do much for the plants in terms of nutrients.

It's not uncommon for an AP system to take a while getting established so patience is a virtue.

I bought 3 kinds of food, one pot of flakes and two different kinds of floating pellets.

I'm a little limited by what is available here, though I have been throwing in caterpillars and other little insects i pull off plants around the garden!

It's probably just going to take a while for the nutrient levels to come up. You probably should see if you can find out what's in the fish pellets (the analysis or at least the ingredients). Right now I'm guessing you either have insufficient Nitrates or an Iron deficiency in the system but I couldn't really get a good look at the plants. Either of these would be common for a new system though.

Oh dear. I managed to kill all of my fish and turn the water black!

I've been trying to find sensible dosing numbers for the seaweed extract during cycling, but without much luck. I found a post where a woman poured the entire bottle of extract into her tank and it was fine. I thought this was kinda crazy, so I only put about 50ml in. Well, that was crazy too, because now it's as black as squid ink and all my poor fish are dead. The really stupid thing is, I sniffed it before I poured it in and thought "wow, this smells like ammonia!", and then poured it in anyways.

RIP, goldfish.

I have a water test kit en route which should come at the end of the week or the beginning of next. The plants seem perfectly happy. Should I leave the system how it is and see what the tests say? Will high levels of ammonia kill the bacteria too?

Will it take a long time for the plants to suck out all of the stuff I put in? Will it concentrate in the hydroton at all?

On a scale of 1-10, how dumb am I? :$

Also, I suspect the water being black will somewhat hamper my ability to test it?

I'd expect it to break down and not cause problems with the media. Is it possible that temperature fluctuations were a contributing factor? I'm thinking by adding this with a clear container if it gets a lot of sun, with dark water, it could get the water warm pretty fast. That would make any ammonia more toxic as well. Of course it could also just be whatever was in the seaweed extract too

I don't think it was temperature. I think the seaweed stuff I used had ammonia in it too. Silly thing is, I could smell it too!

Does the bacteria still survive at high ammonia concentrations?

Still a few days til I can expect the test kit to arrive from Mexico city.

Sorry to hear about the loss.

I've overdone the seaweed extract too, but I don't think all seaweed extracts are made equally, my water went dark, couldn't see the bottom for a few days, but it cleared and the plants & fish were happy.

I'm guessing your seaweed extract had something else in it, chemical fertilizer, etc.

The bacteria will probably be alright but you'll find out when the test kit gets there

I really wouldn't have expected it to kill the fish either though.

Yeah, I was pretty surprised. It turned the water all frothy too.

After the fish died I dropped in a few drops of de-chlorinater and filled up the "bucket" to thin it out. it's stopped frothing and seems to be getting very slightly clearer. Still can't see more than 2 inches down though!

The label on the extract I used is all in spanish, but it seems to include seaweed extract, yucca extract, "amino acids" and inert materials. Perhaps it was an old bottle and had decomposed a little, generating a lot of ammonia. Things degrade fast in tropical climates, as I'm sure Columnmn knows!

I've popped a few more plants in the grow bed to see if they'll suck out the brown any quicker. Somewhere in my attempts to get the effectively invisible fish out of the tank the siphon has decided to it doesn't like breaking, so now the plants are wilting too!

It's all a learning experience, eh?

Sub. Seems like a good start.

Sent from my SM-T217S using Tapatalk

If you're pumping 24/7 anyway, you could switch to Constant Flood by removing the Bell Siphon. If you have a weep hole near the bottom of the standpipe flip the pipe so the hole is at the top. The bed will stay full if the power goes out and this will allow you to fill the fish tank full and not have the fluctuations that you get with siphons or timed flood and drain. All you're doing with Constant Flood is pumping the water in a big loop without siphons or timers involved, but the pumping keeps the water aerated. I'd suggest switching to Constant Flood since you have a relatively small tank and water volume overall. This will help buffer temperature changes in the system.

Regarding the Seaweed extract with Aloe and Yucca - I found this research paper about Aloe which might interest you -

http://www.ajol.info/index.php/ajbr/article/viewFile/35746/59546

Others were saying it was ok in some of the forums but it might depend on how and if, it's processed.

Considering what was in the research paper I wouldn't use that particular Seaweed extract in an AP system (or any other with Aloe or other ingredients that are unknown or have unknown effects). Just get some straight seaweed extract, like Seasol or some Maxicrop if you can.

After thinking about this overnight, I think I'd probably drain the water from the tank and growbeds and start over just in case this stuff isn't broken down. Might as well make a clean sweep.

Cheers

I assume if I drain the water and refill it with declorinated, the bacteria is likely to survive in the growbed?

The water should be pretty good for the lawn and potted plants!

I'm only here in .mx for a few more months, so I'd like to get this stable before I go as the wife won't do much more than feed the fish!

As long as the water is dechlorinated you should be ok. pH and other water parameters can have an affect if they're different than the water your replacing but I don't think this should be a concern.