Aerate the water more? Maybe add a few more airstones?

Ya, maybe get a air pump in there. Keep the light out of the tub too. What are your temps and humidity like?

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Chiceh
Peace, Love & Weed

keep the water cool, keep the light out, and keep things clean, and you won't get algea.

as for cal/mag, i order mine online. it's made by botanicare, and is sold at most online hydro stores, such as bghydro.com.

epsom salts would help with the mag, but the calcium def will get worse; way worse. those spots are just the beginning... check my wet feet thread, first several weeks i went without cal/mag, and the plants suffered. there are some pix of some very sick leaves....

kp

Thanks guys

I am keeping the light off the water and the water is staying cool, I am keeping everything as clean as poss but I still get a bit of algea if I don't use H2O2, I will try and be even cleaner if I can and see if that helps.

I can't get calmag they don't sell it in this country so I will have to buy some calcium additive to cover that.

I have an airstone in there, maybe I should try adding more - I did have it running 24 hours but the last couple of days I set it to timer so it only comes on 30 mions before each flood cycle so thats 4 times a day, is this ok or should it be on all the time?

Thanks again
green

You should be changing the res min 1 once a week, only top up during this period with ph balanced water 5.6, the longer you use old solution in res the plants actually take what they want from the res/solution and by topping it up it doesnt replace the nutes that the plant so desires, this is a major cause to symptoms like yours also there should be no need to feed them 4 times a day if they are in rockwell cubes feed 30mins prior to lights coming on and then 6 hrs after that dont ever feed before the lights go off, the plants will be sleeping. Picture you sleeping in your bed and someone trying to spooon feed you while your fast a sleep its no different. If your room is extremely hot and dry you may need to add a feeding in between. You will also get salt build up in the cubes and its a good idea to give them straight water for 2-3 days after each res change to help bring the PH and PPM in the cubes back to normal. Get a syeringe and remove water from the cube and test it

try bringing your ph up to 6-6.2 and i bet the mag issue will go away, different nutes are available at different ph levels so if your using a complete fertalizer you would be supperised how many defficency's you can cure with a slight raise or lower of ph, this is especially useful when you dont have access to a grow shop or nutes, i have a label off of a ph solution that shows at what ph the different nutes are most available at so if i see something like say a mag deff. i can either raise or lower the ph just a hair to the level where it is most available at

I would suggest getting some literature. everyone here means well but there is really know way to know for sure what your hearing is right. I know everyone is helping but books give you a more scientific position. Anywho check this out

if your using r/o water, you probably need some cal/mag

Can someone tell me which book this is? Thank you.

garden saver

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" The stone that the builder refuse, shall always be the head cornerstone..." ~Bob Marley http://www.rollitup.org/grow-journal...-hawaiian.html