Mustard Green Leaves not Green

[jillybee23]

Good Morning all:

Its been a couple of very trying months but I am finally making some progress. My Tilipias are growing and my grow beds are begining to produce. I have attached a couple of pictures in an Acrobat file. I have a problem in that the mustard and collard green leaves are sort of yellowish green (See page 3)and not the deep vibrant green they should be.

Can someone tell me what the problem is and how to solve it? Thanks

Jillybee

[GaryD]

Hi Jillybee,

It's alway useful to state some numbers......water test results, number of fish, grow bed area.....when confronted with a problem.

The fish seem large enough to be generating sufficient nitrogen, but (depending on your pH) your system may be iron-deficient.....or any one of several other things.

Gary

[jillybee23]

Gary: Here are the current reading:
PH - 6.2 ppm (used API kit and meter, both reading the same)
Ammonia: <0.25 ppm
NItrite: <0.25 ppm
Nitrate: <0.25 ppm

I have no understanding why my ph dropped so low and why my other reading are up. I added some Microbe Life Nite Out II which aid in breading down ammonia. I have added a link: http://www.fosterandsmithaquatics.com/product/prod_display.cfm?pcatid=18390.

I have 27 tilapias in a 150-gallon tank. I have increased the water temp to 72 degrees so they will feed and continue growing. I will do about a 10 percent water change tonight. I have 4 growbed which are approximately 2 ft X 3ft each. Lettuces and brocolli are fine but not mustard greens. I do suspect it may be iron deficiency but don't know how to proceed. Please advise.

Thanks,

JIllybee

[DaveOponic]

I have grown mustard greens and had a similar problem. Initially I thought it was iron deficiency too but pH was also low. Adjusted pH but made no difference. Sprayed the leaves with Dynamic Lifter - Organic seaweed foliar spray. leaves greened up within a few days. I have also used organic foliar spray that contains Humic & Fulvic acid, if I remember correctly these two organic acids have an effect on the root systems, allowing better uptake of nutrients. Can't get Chelated iron here at all so have never used it..... I know that's kind of guessometrics but I think using organic fertilisers in small doses can help solve the problem sometimes even without specifically knowing the cause.

Now here's a similar question someone may be able to answer for me. I have cucumber and pak choi growing at the moment, very well in one AP system bed but badly in another. Both systems are similar setups with normal measurements of everything. The main difference is that this growbed is rather old and probably in need of a clean out. I have recently planted corn in the same growbed and it is powering, doubling in size day by day. Does corn have completely different nutrient needs to the other two crops that are doing so badly? The pak choi has hardly grown at all and the cucumber leaves are yellowing and produced no fruit. (Both veges in the other system are doing exceptionally well)

Dave

[Ravnis]

I have found yellowing to be caused by various defienciency.

Iron is one, magnesium is another. Corn is basically a large grass, so it needs lots of nitrogen and has lesser requirements of other minerals.

I would check your magnesium levels in that poor performing bed. I had a time when I was yellowing and thought it was lack of iron, but added greensand (iron and pottasium compound) and did not see any change. Then I added 1/4 cup of epsom salt to my tank running ~100 gallons and the yellow went away and the fruiting set. Might be worth a try.

I heard someone say they just added some sea salt like you mix in salt water aquarium and that worked for them. Would make sense, sea salt is high in magnesium.

[DaveOponic]

Thanks Ravnis, I'll try that. i have some Epsom salts i used once before.

[jillybee23]

Thanks, I will try some sea salt and let you know!

[jillybee23]

I added some sea salt to the tank and I can see the change in the leaves. Thanks for the help!