kills everything i plant

[wally]

i have two questions, but first i have been raising plants using hydroponics (built all my own beds) for ten years or longer. everything was perfect. then i moved. now i have built two new gardens. and lot of alga formed (a new problem for me but i did build these beds a lot different then my first ones) so i tore them apart and cleaned everything with clorax, painted the outside of the beds black to eliminate the light to the water storage. now one bed works beautifully, one kills everything i plant. i am presently tearing the bad bed apart again and flushing everything with clean water. is this the thing to do?

can there be clorax residue remaining causing the damage?

second while dismantling the bed i noticed that the pea gravel is staying damp between feeding, therefore the roots are also remains damp (not wet, just damp) is this a problem? if so why only one bed?

i pump water twice a day (have done this schedule for years) for about 1 hour at a time. there are overflow drains in the top beds so excess water drains back into holding tank. there are also drains in the upper bed that drain all the water off the roots, after pump shuts down, in about 1/2 hour. anybody have any ideas? now back to work cleaning the bad bed until i hear from, hopefully, all or some of you. thanks how does one join this hydroponic club? wally i believe you will get my address but if not try RuthK@Quintex.com. (life isn't east for a boy named ruth so i go by wally)

this is wally again, forgot a couple of important facts that should have been included in my question. each of my gardens have their own pump and their own water/nutrient holding tanks (50 gallons) the only thing common is the timer that turns them both on and an hour later turns them both off. thanks again---wally at ruthk@quintex.com

[Ron]

Yes

No

Damp should be OK but check your draining for that bed. Flow control valves on every bed can equalize the levels to each bed. Then make sure all the beds drain completely before watering again.

Well then forget what I said up their and switch one garden nutrient tank that is doing good and use that one for your problem bed. If the same problem continues then that bed is possessed so call an exorcist.