My DWC grow- looking for some assistance

So I'm making the switch over to dwc from coco coir. While I was happy with the results from the coco coir, I hate having to worry about over/watering. So I built a top fed DWC unit, similar to the stealth hydro ones. Before I switch my last batch over to flower I took some clones, which I'm using in for dwc. But so far I'm having some problems. One problem I'm having, which just resulted in a plant dieing (maybe I gotta see if it died when I get home), is the manifold getting clogged up. I'm using 1/4" hose for my top feed only because I couldn't find a manifold or splitter for 1/2". The other issue is my plants (the dwc plants only) have dark brown spots on them. my water temp is on the warmer side usually, somewhere between 70-73. I need to either get a chiller, like a full sIzed chiller or one of those ice probes. I'm also planning on using styrofoam to line the inside of the Rubbermaid tote.

And this maybe a dumb question but i better ask now, Is it possible to grow 6 plants till harvest a unit similar to the stealth unit? I'm only planning on vegging for 4 weeks. Plus strain is jack herer. Thanks here's some photos.

Im sure its possible, but it will be alot of work. Im doing 2 in a 18 gallon rubber maid. Ive heard issues with 2 out of the 6 getting nute deficiency, but if you add nutes it would neg affect the others. Other than that, I'd say keep an eye on water levels in flower, 6 plants should be drinking fast (I would imagine)
Are the plants going to grow into each other basically? Never grown JH, but will light be an issue?
Good luck.

It's only a problem when something goes wrong - which is why I switched from RDWC to Hempe buckets. A problem with 1 plant effects all the rest with the cure. If 1 dies and the roots are all intertwined then root rot problems begin; If one hermies and you have to remove it - can be a problem; if 1 has a deficiency then the fix might give the others a toxicity problem. Also 6 plants with 4 weeks veg in a hydro system will usually result in massive growth. For example my 4 plants in RDWC at 4 weeks from seed resulted in 26" tall plants (Indica's). By the time all was said and done 2 were removed 1 - male, 1 hermied leaving 2 good females. the 2 females were about 72" tall (including buckets) and spread out to about 4 feet wide. So depending on how tall they get will determine if they will fit in your space. I would only fit 1 or 2 in that thing for full term and flower them when they are 12-15" tall otherwise I think your asking for problems with space, humidity, air movement, light penetration, and so on. Just my experiences.

Yeah I'm looking into doing sperate 5gallon buckets but then you have to do each plant individually which can be a lot of work. Hey do you Guys know what those brown spots are?

I just started doing DWC and was getting brown spots at the bottom of the plant and all the leaves were yellowing. My PH was too high. I lowered it and two days later it was fully green and growing again. what is your PH at? Your spots look like mime did but your plant isn't as yellow.

Hey thanks for the reply, yeah I suspect that was my problem as well, I've noticed sometimes it takes a little while for my ph up to take full effect. Like Ill add the up and put my ph pen in and I'll watch it go up, but I noticed if I wait 10 minutes or so with the air and pumps going it will be a little higher.

Veg'ing under 14,000k 250 mh.

Just bought a ice probe

Supz Nodg. I've done DWC for 2-3 years now. Started in totes and still use the same one as far as veg goes. Can you take a pic or two of your rez? With the roots and everything. Your nutrients settled to the bottom thus clogging your pump and throwing off your PH levels would be my guess. I use at least 2 air stones in my reservoir and for visual reference picture some boiling water...really aggrivate that shit yo! That ice probe looks pretty sweet. I dont usally have water temp issues, but yea nything over 75F will straight up destroy. Btw....are your girls in rockwool errrr what? Is it a color thing from the coco? Shouldn't be brown and funky looking like that. Cover them up and dont let light or w/e touch them. Equals root rot. With top feed you'll have nute buildup on top of your medium sometimes as well so you may have some algae growth/etc because thats just a ripe area for things of that nature to thrive if left uncovered. You have air movement in that cab yea? PH levels should be 5.8 +/- .2 The more info you throw at us...the more we can help