Backyard Aquaponics
A place to discuss aquaponics

Don't bother. The warning is typical of our hypersensitivity to any possible safety issue. Your drive to purchase it was almost certainly far more dangerous than the product, even if you tossed the stuff in the air in a closed room and breathed the dusty air for an hour. The dust should have washed off when you washed your gravel and any that remains will settle out in the growbed eventually.

Assuming that the gravel is silica-based, it will also not raise your PH to problematic levels, so that is good, too.

yea Thats why i used it to.

but i would try out some more goldies. see if its the fish.
if not might be the medium.

now you dont have to buy clay-balls(hydrotron), you can get Aquarium Gravel, thats what i use most of the time.

Hydrotron is for people wanting a Light option, to not have a 100 pound grow bed.
but if your set up with gravel stay with gravel, the bacteria love gravel more the hydrotron(more surface area and darker) add some red worms and there you go. thank you for your time, and as always with me and AP... take With a grain of salt.

-dank

Thanks for the replies!

Yeah, I think I will get some more fish this weekend and see how that goes and then think about drastic measures. I'll post updates as they come about.

Make sure to salt to 3ppm as the feeder goldfish are often infected with var stuff. Also find out pet store delivery date and get fish at least a few days after that so they are not twice-stressed. After a week or so, drop the salt to 1ppm....

+1
great tip

Well after being away from home for 5 days because of work, I returned to find that both of my remaining goldfish were alive and that the plants were still growing! I think the fact that those two survived likely indicates that it's not the gravel that was killing my fish and that it was just a bad batch of cheap goldies. All of this eases my mind!

While on the road I was having odd AP dreams, obviously this past time is occupying much of my conscious and unconscious thought!

Before I left, I decided to rig up a super duper low quality reflector in hopes to limit the amount of valuable light that was escaping the system. To achieve this I draped sheets of aluminum foil over the tops of the lights and it makes a visual difference. Hopefully my plants appreciate the effort.



Being anxious to provide my plants with more food, yesterday I went to the pet store in Durango and purchased 15 more goldies. I have put 13 of them in the FT and kept 2 in a small fish bowl that I purchased for backup/ to spruce up my tiny house.



Prior to adding the fish I removed all of the gravel from the bottom of the FT. I had put gravel in when I was first getting started only to later read that this is generally a "no no". While removing it I learned why! LOTS of waste had built up in the little gravel I had and clouded the water pretty good. I strained out the large chunks and let the system run for about 2 hrs to clear up the water a bit. It cleared up nicely. I also threw in some pieces of left over 3" PVC so the fish have plenty of places to hide.



Salted the tank to ~3ppt before adding the fish (thanks for the tip hydrophilia!). All of the new fish survived the night, which makes me hopeful.

Levels are all looking good. Hoping to see a bit of a rise in the Nitrates within the next couple of days as the fish eat and poop more.

Happy growing!

nice to know that it might not be the rocks, that makes buying media way cheaper.

some times its great being wrong!!
i am think about using some pond pebble from home depot: www.homedepot.com/webapp/wcs/stores/ser ... key=Search

i hope these will be safe to use

good times forshure

-df

Yeah, I'm pretty stoked that it seems to not be the media... I would like to have a bit of a lighter GB at some point because right now I have 200lbs of gravel in my small bed which is about the max that my shelving can hold, not to mention the GB container itself. It is nice and cheap though at ~$5 for 50lbs!

So I finally found an Iron Chelate which I think will work in my system, but I wanted to run it past folks before I put any in in case I missed something. Its Grow More Organic Based Iron Chelate 10%. It contains Nitrogen, Soluble Potash, and Chelated Iron. It says that its "Derived from Iron Hydroxyethylenediamine Tetraacetic acid (Iron HEDTA) and Potassium Sulfate.

Is this safe to use in AP?

Yes, but only in very small doses. The potash will cause the pH to change.

How small of doses are we talking for a 25 gal fish tank? a pinch, or a teaspoon?

How about putting a gram (or a half-teaspoon) into a gallon of water and testing PH before and after? That should at least tell you what is safe. I expect a pinch each day would be safe and would handle the iron deficiency pretty quickly. Note: goes in the growbed, not the fish tank: is probably better to avoid the fish eating it directly...

Thanks for the response Hydro. My ph was 7.8 prior to adding the iron, and 2 hrs later is was still 7.8, so that's good news. I am assuming that potash will have a cumulative effect in the system? So I should be careful with how frequently I am putting my iron in and be doing water changes to get rid of it? Is this correct? Or or will the plants use it?

Potash is the common name for quite a few potassium containing compounds. Some of these are high PH. The plants need the potassium, but you don't need the PH high and, in fact, it will tend to lock up important nutrients such as iron. Best PH is more like 7ish. Add the potash-containing stuff and test to make sure it is not raising the PH. I would say test once after the first dose as you have done, then after another two doses, then after another four. If you haven't seen a change by this point, don't worry about it any more.

The plants should use up the nutrients you add, then you will eat the plants, but you could always water other plants with water taken from your system if you are concerned about salts building up.

Water changes shouldn't be necessary in an AP system... and the plants will take up the trace elements as required...

There's really no need to be dosing your system more than once a month... with anything... if you are... or your plants are requiring it....

Then you have more fundamental problems that need addressing...

Use a general purpose trace element supplement once a month... like Seasol/Maxicrop.... liquified seaweed.... either foliar fed, watered over the growbed(s), or even directly into the tank/sump...

Use the chelated iron only as/if required.... as your system matures, you should hardly ever need it...