Can anyone tell me what black spots on leafs are .

[Raymond Nunez]

  Does anyone have a clue what these black spots are on my tomatos these spots are also

  on my squash and pole beans .

  My system has been running for seven months i have a 300 gal tote with 12 2" talapia

  with 3 grow beds 6' x 4' planted to the limit with lettuce, starwberrys, squash , beans,ect .

 Also my squash has lots of flowers but does not fruit flower wilts and fall off .

PLEASE HELP . 

Any info will help.

[Joe Bifano]

It might be phosphate that you need.  I have a 6.6 ph so I had black and purple leaves and then started to add phosphate and they can back.  I am getting purple leaves again so I am adding more now.

[Bart]

I notices some similar spots on mine a while back, they have since gone away and the plants are doing very well. The only changes I have made would be the addition of some iron, and the fish have grown considerably - can't say which of those two might have helped but I wouldn't panic if I were you.

 

 

[Jonathan Kadish NYC AA Chair]

Could be a Magnesium deficiency. This can be treated with Epsom Salts in a weak foliar spray solution or ad a little to your fish tank. Worth a try anyway.