RDWC with waterfalls; branch or homerun style?

[Norville Rogers]

Hi everyone. Long time lurker but i never post because i wanted to make sure i knew enough to give proper advice first. I have a few grows under my belt now and just did 4 strains in a 4 site 1.5 inch abs RDWC DIY undercurrent in a 5x5 tent. I do undercurrent with a chiller but used a single pump for both and also bled the feed line a little back into the buckets to create a waterfall that was basically incorporated in case i wanted to pump from the res instead of return and figured the extra DO might help. The flower system i've been using worked well until i introduced a new strain that overwhelmed the others. Even with extreme training i could keep the canopy height even but ran out of room horizontally for all the plants to flourish. I know what the small yielders were capable of and that it was just a matter of space and even with 24 inch centers one of the strains roots grew through the pipes to the next bucket and although it didn't clog the lines i decided to upgrade everything and use this system for veg in my 4x5. So, my question is how i should design my new system because i have irregular needs. Most Undercurrents have what i consider "homerun" style setups with the returns and pump to the res. The waterfall method pumping from the res to the buckets is what i wanted to do now, but am not sure how to do the returns the best way. Sometimes i see them setup in the homerun style, but other times what i what call "branch style" where each bucket connects to a common gravity return line to the res. If i were to use the branch style so that water doesn't need to travel through each bucket, i wanted to see what others thought about the flow rates before i started cutting expensive plumbing.

I have an 8x4 tent now, 4 13 gallon ez stores and res, 3 inch abs with 3 inch current culture bulkheads and a whole bunch of assorted flexible couplings so i can alter things or disassemble for cleanup. My problem is a 4 site in a 4x8, and how to branch them the most efficiently. I have a Jebao DCP-8000 pump for the feedline that does about 2000 gph that i was going to blast the hell out of the buckets through pipe reducing and pressure, but also bleed the line to the chiller. Because it's a DC pump i can adjust the speed (watts) and was using a 1000 GPH Jebao on full before so even at half speed the flow rate should not a problem to me. The 3 inch returns is what worries me even though i paid a pretty penny for overkill hole sizes to avoid headaches. In the pictures i have my old system for an idea what i'm used to, and the 4 basic ways i can do my return lines also with the feed lines under them.

I usually do A, but was leaning towards one of the other 3. I like B for the simplicity and easy access but wondered if there would be uneven drainage rates. D would also be ok but is harder to access and requires more plumbing. I also have the problem of getting 3 inch pipe through the tent to the res in between zippers that might require a few elbows to get around so that's a small deciding factor too. 3 inch pipe holds alot more water than 1.5 too but i'm guessing (and hoping) it's roughly 55 gallons (5 x 13 gallons with 10 gal each plus return pipe volume) like my rain barrel and if i'm a little short i'll top it off from the top off RO barrel. The last system was 30 galllons. I have the CCh2o lids and netpots now too if it matters.

So, would B with the single return line branch be sufficient drainage with 3 inch returns, 1 inch to pressurized and reduced feedlines, and 1k-2000 gph pump? Is a single exit each bucket sufficient drainage too or do i need to add a second bulkhead to each (i have 9 bulkheads)? I'm assuming B although not optimal is fine and i'm overthinking it. Thanks.

 

[Mr. Mohaskey]

I run the "C" option in a 5x5 tent. Biggest problem I had is getting access to the back left site if needed. Drainage wise it works without a hitch, although I have 2" return pipe and got clogged from the roots. Poor planning on my part.

 

[Norville Rogers]

I run the "C" option in a 5x5 tent. Biggest problem I had is getting access to the back left site if needed. Drainage wise it works without a hitch, although I have 2" return pipe and got clogged from the roots. Poor planning on my part.

Thanks for the input. I 100% agree with the poor planning part that has been my problem and find i learn as i go and add on inbetween grows. To help with the roots clogging the lines i had 1.5 abs threaded bulkheads that i put an abs tee on the INSIDE so that there were 2 points of entry to the bulkhead instead of 1. The first few weeks of flower when changing the water i train the roots to grow away from the holes and i thought it worked well until i noticed the roots had grown all the way into the next bucket like in the pic (during cleaning, don't mind the polluted water). In the pic with the roots outside the bucket you can see the "umbilical cord" that went to the next bucket. I usually flip a valve on the pump and drain to a sink, and when the water level reaches the top of the bulkhead i shopvac the remainder out. I also understand the dilemma of accessing the plants because i've upgraded tent sizes a few times and the openings are allways at different places. One of the reasons i liked the B method was because i'm now using the current culture lids and because of the porthole it makes gaining access to the buckets harder when using a shop vac and with this layout it's a straight line. Access to the canopy mid flower on is important when using RDWC and a scrog so i planned around that part but the darn 3 inch pipe fitting inbetween zippers at the level i need it is turning out to be my hardest part and dictating my returns. Last time I upgraded from a 4x4 to a 5x5 and it made all the difference in the world last time so i'm hoping the 4x8 gives me more room to breathe and maybe throw an AC in there instead of porting it through an opening.