it seems I did something wrong . I seeded radishes and asia salad both is coconut and directly in the clay balls of my grow beds. They sprouted and started to grow but after a while the stem is getting too week and it breaks off. Moreover, I have also some little bugs eating the leaves. Is this a fungus? I was just reading that fungus can grow when the media is wet in the surface something that is my case. Probably I had to put more clay balls! Now what? how can I get rid of a fungus that probably is now everywhere? Can it go also to the fish? The bacteria indication looks great and I have no ammonia spikes so far.
One more thing, my siphons are still too big for my small grow beds even though I replaced the pipes with the smallest I could find. If I regulate the flow so to get them breaking at 15 min, the flow is too little and they dont break, they just overflow. Now they break every 6 min. Is this also bad?
If your media is turning green and slimy on top, it's not fungus but actually algae. You want more media so the surface of it stays dry.
Siphons kicking on/off often is ok, if they are working and the bed is flooding/draining I would leave it alone.
As to the damping off and bugs and whatnot. Indoor growing can have issues with much of this. You can brew chamomile tea and cool it off and dilute it some then put it in a spray bottle and spray your seedlings before the damping off happens since once the stem pinches off and the seedling falls over it's too late to save it. Once the seedlings have two true leaves in addition to the first seed leaves they are usually safe from damping off. Having the surface of your media stay dry will also help. And if you can stick an oscillating fan in the room for some air movement and ventilation you may do better. Do you have enough light? Seedlings getting tall and spindly and weak is often a sign of not enough light or the light is too far away.
Since I can't see the bugs you are talking about or the damage, I don't know what to tell you there. Perhaps sticky cards would help?
Valentina, Can you post pictures of the algae/fungus and of the plants?
I dont see green algae, but the medium is definetelly wet on the surface. I dont have enough light and some leaves became white. I ordered from e-bay some LED grow lamps and still waiting. A fan seems definetelly good idea.
Thx for the pictures. Yes, the bed is too wet. Aim for the top layer of balls to be dry. If it stays wet and you add light, you'll get the algae growth. Green algae can actually look black.
The white specks are white flies and the bugs on the leaves look like aphids (they're related). If they're aphids you may eventually see ants hanging around because some ants culture aphids for honeydew just like we culture cows for milk. Honeydew is a sweet excretion the aphids give off.
I have the best results spraying with neem oil and cayenne. Here's what works for me:
Start with neem oil only; mix according to directions. Spray 3 times the first week & see what happens. If that gets rid of most of them, taper back to 1-2 times/week as needed. When they're gone, spray any time you see them re-appear. It won't hurt the fish. If the neem oil along doesn't get rid of almost all of them pretty quickly, mix about 1/8 tsp of cayenne into 16 oz of the neem oil mixture and spray. That should take care of nearly all of them.
The weak plants are probably a combination of the low light, the bugs, and over-watering, but it certainly won't hurt to follow TXLynx's suggestions about airflow and chamomile. I'd never heard of the chamomile trick, so I'm going to remember it in case I run across damping off in the future.
Yea looks like not enough light and way too wet. If you take care of those too things you will likely see a huge improvement. I don't think those are damping off, just spindly and weak. Light and air flow help those situations.
More media will probably help with the bug situations too though you might just gently wipe the aphids off if you can without mangling the leaves.
I'm cautious about any oils where it will contact system water much since any oil slick getting into the water will not be very good for the fish or bacteria so if you use any neem I would recommend waiting till after the media level has been taken care of and perhaps doing something like a drop cloth with paper towel or newspaper around/under the plants during spraying to catch the over spray and keep it out of your system water.
Thank you both so much! you really help me a lot.
I think it's too late to save most of the plants, so I was thinking to take them all out with the clay balls that carry the white flies, add more medium, light and air and put new seedlings (I have saved some). In case the same sysmptoms happen again (hopefully not!) I can try the chamomile tea, neem oil and cayenne. Sounds good?
Just to know: in what kind of store can I find neem oil?
Also: do you use artificial light? What is your opinion about blue-red led growlamps?
Neem can be found at garden centers.
I try to use natural sunlight as much as possible but there is a group here about indoor growing and I think another one for artificial lighting so you could search for them and see if anyone can give you some good tips there.
What about Murray's method for the bugs;spraying the leaves with diluted melassa?