Backyard Aquaponics
A place to discuss aquaponics

you can put plants in now..
you might have to supplement with maxicrop with iron until the ph drops..
when you get the fish, put the bag in your tank until the temps are equal, then gradually add a little system water to the bag to get the ph equal, then release the fish

Ahhhhggggghh!

I put in 9 of my starter plants as a test, and flame-on, cripsy !

In about 2 hours they were burnt to a crisp! The plants I used were: Bok Choy, and Oakleaf lettuce. Are there any plants that are more tolerant to high PH???? My chemistry is: NITRITE=0, NITRATE=20 ppm and PH is over 8.8 (off the chart)!

Any ideas? Should I dose my empty FT with ammonia again, and watch it cycle a few times with hopes that the PH will drop?

Perhaps it is time to put some hydrochloric acid in the system to drop that ph. The stuff it breaks down into is actually good for fish. Then, setup a topup barrel that you can use to correct the to water with HCL. Then when you topup, the water will be a better ph. In the future the ph of your tap water may be considered a good thing though.

Tell me, Ronmaggi-

Where to get Hydrochloric Acid? I searched the Petco website and found a bottle of Kordon "PH Decrease" for $5.43. Treats 2,800 gallons, so for my 110 gallon system, seems reasonable! This product uses citric acid, but I read an aquaponics forum post that said not to use citrus fruit for PH adjustments. They cited the fact that hospitals use citrus as an anti-bacterial disinfectant. I don't want to kill my precious bacteria!

There was also a second product, "PH Down", by API. This comes in a tiny 1.5 ounce squeeze bottle, and uses sulfuric acid.

Hiya Jon, all pool and spa shops sell HCL, I got mine from the hardware store, it's used for cleaning cement off bricks too, cheap as chips.
Don't forget to add it to your top up water.

Right, some Muratic Acid (HCL) cheap by the gallon from hardware or pool stores. Follow the precautions and handle it carefully. Adjust the pH of your top up water or change water and let it stabilize (mix or bubble for a day or so and test again to make sure the pH is stabilized) before using it in your system to gently bring the pH down by 0.1-0.2 per day. If you use the acid directly in a system you are likely to cause pH bouncing and kill off bacteria and any plants or animals already in the system. If you can get the pH down between 7.2-7.8 that is all you need to do in the system and then it will likely come down naturally just fine.

Might be worth a small dose of ammonia again to keep the bacteria going until you get the pH down below 8 and then think about getting fish.

You mention of getting 22 bluegill and 2 catfish to put into 2 55 gallon barrels with only your NFT and vertical plantings as filtration!?!?!?!?! I'm hoping you also have some other additional filtration since the towers and NFT really don't provide filtration. But uh, I would say that is way too many fish.
What kind of catfish? Channel catfish are too big to keep in a blue barrel for very long. I don't even like to keep channel catfish in a 100 gallon stock tank for more than a short time. Personally I wouldn't try to grow out channel catfish in anything smaller than 300 gallons. Channel catfish can reach 18 inches in less than 9 months and they can be over 3 lb in a year under good temperature, water quality and feeding conditions. A blue barrel is only 24 inches across so a growing out channel catfish in such a container is going to be severely stunted. I know people who have grown channel catfish out in IBC tanks but I still personally like bigger tanks for them.

If you are talking about a different kind of catfish (like maybe pleco or bullhead) I don't have experience with them.

As for stocking bluegill, During your first season of operation, I would still recommend only stocking one fish per cubic foot of media filtration you have. Once you are past your first season, you can decide for yourself if stocking up to 3 times that many bluegill is appropriate (since most bluegill are going to be harvested at 1/3rd of a pound rather than 1 pound each.)

A Natral Way To Bring Ph Down Is Lemon Juice. Small Amounts With Ph Is The Way To go.

Lemon juice does nothing. Speaking from experience. In the ammounts needed to do anything, citrus oil would cause problems.

I agree, in a system where the pH needs only a tiny amount of minor pH adjustment, lemon juice might not do any harm and may almost work.
In a system in Southern California, where the tap water is more like liquid limestone than it is here in Florida, anything with any citric acid is a BAD idea.

I personally don't really recommend the use of acid for long term pH adjustment but for initial system start up and to get past the initial horribly high pH of really hard liquid limestone water, the use of HCL is warranted. Once you get your pH down below 8, it may be worth looking into rain water collection and/or an RO filter for at least a portion of your future top up water. A little bit of hard top up water can be a useful pH buffer for the system but you don't want you pH that high.

Many people will insist that a pH of 6.5 or 6.8 or 7.0 is ideal. The truth is a pH that allows your plants, fish and bacteria to grow and you can maintain at a relatively stable level is going to be what your idea pH is. If you are having to wrestle with acids and bases and causing your pH to bounce or fluctuate wildly you will be causing far more damage than good.

Avoid products with citric acid in them. Citric acid is antibacterial.

JG, what's the pH of your source water?

Thanks for all the info, guys!

To answer your questions,

My tap water reads at PH=8.0 after sitting about 8 hours.

My NFT system sits above PH=8.8, that's as high as my test kit will read.

My system has no fish, I have been dry cycling using household ammonia. At this point, my ammonia goes to zero in about 48 hours, the nitrites go to zero in about 96 hours, and I have about 20 ppm of nitrates. I have tried adding a few plants, but with PH over 8.8, the plants die within an hour or two.

My NFT "water falls" into the fish tanks, the fish tanks syphon into a home made swirl filter (for solids), and then the swirl filter "water falls" into the media filter. You can see a photo of the swirl filter and media filter in the last picture of the first page of this post. The 5 gallon Homedepot bucket is filled about 1/2 way up with hydro-corn, and shaded with a bucket lid. A hole in the lid accommodates the swirl filter overflow and the drip tubing line from the submersed pump up to the grow towers. I also have a bubble stone in both fish tanks.

I expect that I should be growing bacteria, not only in the 3 gallons or so of grow media of the bio-filter, but also the 20 feet or so of poly-rope dangling down the vertical tubes, the 12x one-cup or so of grow media in each grow pot of the horizontal NFT circuit and the 76 root balls of my 76 plants.

Nice idea about rain water collection, EXCEPT, Southern California is classified as a desert, and we rarely see rain!

The original system design https://www.engineeringforchange.org/news/2012/03/14/how_to_build_a_vertical_aquaponic_system.html did not include any bio-filter or swirl-filter. After I built this system as accurately as I could, I realized that I needed these filters. The best data that I could find suggested having a ratio of 4:1 of plants:fish. With 76 plants, that comes to 19-ish fish. I assumed either a few fishy-fatalities, or I harvest 2-4 fish when they get larger in size, hoping to stabilize the system at 18-20 fish. This jived with suggestions of from 1 fish per 4 gallons to 1 fish per 1 gallon. 110 gallons/19 fish = 5.7 gallons/fish.

The most similar setup I found was some commercial NFT setup with over 1,000 gallons fish tank. They were using these little plastic bean-sized doo-dads (I forget the name) for the media of their bio-filter. He said his 10 gallon bio-filter was more than enough!

Sounds like this is going to be an ongoing pH battle, JG. I'm thinking since you're fully cycled and still sans fish that the muriatic or hydrochloric acid is the way to go. And if that isn't readily available, hit the local hydro shop for some pH Down.

What are the chances that you've been using ammonia that has soap/detergent in it as opposed to pure ammonia?

Something to consider for the long run might be a reverse osmosis system. Double check with your local water treatment plant and see if they're using chlorine or chloramine. If chlorine, an RO system with proper filtration and valved for either 75 or 150gal/day with an appropriately sized storage tank for your AP AND drinking needs would get the job done. Hey, if you're going to spend the money YOU may as well benefit from it directly as well. If water treatment is using chloramine, you're going to need to include a DI filter as well.

I just upgraded my 10 yr old 5 stage system with a DI filter. My post RO water was good @ 4ppm total dissolved solids but I had to deal with chloramine as well. After the addition of the DI filter, I'm down to 0 ppm TDS. I'm also not losing fish anymore... Pre-DI it tested 2 7.0 pH. Post-DI it's down to about 6.2. My little basement system is currently being driven by a single goldfish and 3 plecos. Tested yesterday, pH was 6.8, ammonia was between 0 and .25, nitrites were 0 and nitrates between 60 and 80. I recently redesigned everything and pulled all of my tomatoes so the only thing in the GB at the moment is cuttings in the process of re-rooting.

if your pH is rising, then either there is something in the system that is bringing the pH up, OR you have something anaerobic going on that is elevating the pH.

Is there any algae going on?

How often are you emptying the solids out of the swirl filter?

Algae can do some crazy things to pH (often times when mats of it start decomposing along with blobs of solids in a anaerobic mass.) Rising pH is often the first sign of anaerobic decomposition.

Yes , after my Nitrites spiked I got a lot of algae. I read to shade them, and then the algae would die off. I did and they did (shade,die), but I still have a little.

I have only drained the swirl filter once, when I had over filled my system. I don't have any fish to make solids yet! I have noticed that algae is collecting there though!

1) Do you/how often do you recommend I drain my swirl-filter BEFORE I GET ANY FISH?
2) After I get fish, how often should I train this swirl-filter?
3) Any recommendation on what kind/how many fish nets to get? If I had one, I could scoop some algae from the solid-filter.

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BTW: My last post, I claimed tap water PH>8.8. I think that it may be coming down, and is now actually 8.4. I have been treating my top-off water with PH down (sulfuric acid based) to a PH=7.8. I have only done two 3.5 gallon top-offs this way so far, yet.

1) If there is gunk collecting in the bottom of the swirl filter, you want to remove that gunk. Hard to say with no fish since I don't know how much gunk is collecting.

2) once you get fish, if you see gunk starting to collect, then you probably need to be removing it every 1-3 days. If you leave it too long and it goes anaerobic, you will understand why you want to remove it more often since the smell of the stuff you drain out into a bucket is likely to make you gag.

3)type and how many fish nets will depend on type of fish and how you will be storing the fish nets (what kind you get) The cheap ones from the pet shop, I recommend you get several extras to keep inside or at least protected from sun. The ones you have out by the system will have only a limited lifespan since sun and/or sterilization tends to break them down and they will start falling apart after a time so have a couple spares. Make sure whatever net you get will be appropriately sized/shaped for your tank and the fish you will be keeping. A bit round fishing net is not likely appropriate to even fit into a barrel and will likely have too big an opening for catching small fish anyway. The little green nets might be great for small aquarium fish but I've had problems with small catfish getting their barbs caught in the nets (to the point where I actually hand scoop new catfish fingerlings out of the transport bag to place them into my system because trying to untangle the poor little things is so stressful to me and them.) Other than those tips, I don't have a particular net to recommend.