Like I said, Im several years out of date, but it was generally accepted in reef and saltwater tank circles that the bubbles were not what actually contributed most of the aeration. Its the stirring of the surface of the water and the mixing of water from low in the tank up to the surface that was most important and most effective.
The super fine bubbles can actually change the PH of the water if there is a hi concentration of CO2 in the air. On the other hand, the roiling or “fluming” of the surface - without the super fine bubbles) was what was most effective - without the negatives the bubbles caused. Waterfalls are also excellent compared to bubbles.
Thats where the hydroton or other media with lots of surface area that has water flowing across it comes in. Its the same effect that makes NFT so good. Tons of aeration occurs in those situations compared to using fine bubbles.
Try looking up ‘fluming’. Its just basically taking water from low in the tank and pumping it up to the surface so it just breaks the surface, causing a nice roil.
Now, all of that said, obviously regular air stones are not all that bad or people would be having more problems.
For me its as much about saving money as anything else. That plus I just like to DIY where I can. Keeps me busy
The GH plumbing kit arrived and I have been testing it out. I am disappointed that it is not really any better than my DIY setups as far as the volume of water being pumped. It also has no more and maybe even a bit less “head” generated. In other words, it wont pump the water quite as hi as my home made version. It does work though and is a lot less trouble than making one yourself and is cheap enough to make it worth doing. My DIY version takes a bit of fussing and fiddling to get max performance. You can save maybe $5-$8 by making one yourself, but I dont think thats worth it for the poor pumping volumes.
The main problems with both mine and the GH pumps is they have limited lifting capability and very low volumes. Both need to have the lower end at least 6" under the water level in the rez, and can only lift the water maybe 10"-12" before the water volume drops to zero. Those two thing limit the recirculating aspect and severely limit where you can locate the rez and how far below the hydroton container the water level can be. They both use a lot of air for the volume of water moved.
So, now Im going to build a Geyser type air pump and a pneumatic ejector pump. Either of those is a more complex build, but but still pretty simple. They pump a lot more water and have much higher lifting heights and will work in shallower water, for the same amount of air used. Both of these pump water at a 1:1 ratio for the amount of air used. The GH is probably more like 20:1.
Costs should be in the same range or maybe a bit less than buying a GH plumbing kit. Basically, the pneumatic ejector pump is a geyser pump with a simple one way check valve that makes it a bit more efficient and gives it a much higher head height and flow rate.
I can post links and more info if anyone wants. I will post pics of my prototypes after some testing. I have everything I need except something simple to make a one way check valve. I need the right sized rubber ball or something to make a flap type valve from…
Oh - forgot - Im hoping that using the geyser or ejector type pumps will let me remote mount my rez and make it much easier to fill/drain. It should also help keep the water cool and have much higher circulation rates.
Oh man, I have found something that has me seriously considering doing ebb and flow! How about ebb and flow with just an air pump - NO mechanical water pump needed?
I built a quick and dirty version of his airflow pump that he shows near the end of the video. It doesnt require any check valves and it works much better than any of my versions, including the geyser pump I just made. Very simple and pumps great! Mine is on a smaller scale using 3/4" PVC and 1/2" CVPC pipe. Greay head height and three or four times the water flow rate.
Now I need to head off to HomeDepot and get some more fitting and pipe. I need to add a bell siphon and I think I can do a super simple and super cheap ebb and flow!
Here are the parts. The only mildly dificult part is drilling a hole in the 3/4" PVC ell bow so that the 1/2" CVPC pipe is a tight fit. The airline connection is just a jury rig that goes into the the other leg of he ell bow. Air goes intot he ellbow
and flows down the 3/4" pipe forceing water back up the CVPC pipe.
Oh. I forgot one of the best features of the geyser, ejector or the airflow pump at the end - none of them will pug up with salt build up. You would still want to keep roots out, but that will be no problem with a remote rez.
just make sure the table slants toward the drain, and that is all you need. A magnetic pump will not fail easily. when the table reaches its maximum height, the water will fall back to the rez adding oxygen.
Many people report issues with the submersible, mechanical pumps heating the water too much. That forces them to add water coolers. The air pump will add far less heat and it can be remote located and cooled pretty easily. Plus, its cheaper and simpler - fewer parts to go bad and lower initial cost and zero maintenance. Mechanical pumps are also subject to salt build up and blocking due to plant matter getting sucked inside.
Yeah, but you need a timer to cycle the water pump dont you? This system needs no timers. You can adjust the fill/drain cycles by changing the air pressure and the siphon rates so that its all automatic with no electrical times or gizmos other than the air pump.
Oh, I wont need to do a table. Im still planning to just do two plants. Each will have its own bucket feeding back into the siphon chamber and then the rez with the airpump.
Im also picturing being able to re-direct the pump output so it goes back into the rex for mixing nutes, but that may be more trouble than its worth.
For water changes, all I will need to do is pull out the air pump and go dump the rez, then mix up new nutes and stick the pump back in. Wont have to do anything to the siphon chamber except clean between grows.
Even if I dont do ebb and flow, this new pump works at least 10 times better/faster than the GH plumbing kit - and it will never plug up with salts, so that by itself is a huge step up.
Im trying to decide if I can do ebb and flow as far as fitting the plumbing, rez, etc into the space I have to work with, or if I am going to stick with my original plan. Im also a little concerned about power failures.
Am I right in thinking that if I did the normal watefarm/DWC type thing, the roots would at least have the lower chamber or the bucket with water in it if the power went out. Even if the air stones and drip system, pumps, lights etc all quit working for a few hours, the roots would still have water and the plants could survive - for a while.
On the other hand, if I did ebb and flow and the power goes out, all the water will drain out of the hydroton in the grow pots/buckets, and the roots will have no water until the power comes back on.
One solution would just be to top water by hand until the power came back. That would not be all that hard as long as I was home and could start before the roots dried out too much. But what if Im not home and cant get back for several hours? Would there be a problem if I set the minimum water level in the pots so that it left say an inch or two of water when it drained? Would that defeat the whole "ebb’ part of ebb and flow?
Im thinking right now of using two 5 gal buckets - one for each plant - with a separate 15 gal rez that controls the cycling and the water height in the plant buckets with a bell siphon. By adjusting the bell siphon, I can set the min and max water levels, and the drain rate in the grow pots easily with no electronics.
So - would it be ok to leave a couple of inches of water in the bottom of a 5 gal plant pot full of hydroton? Right now I guessing that the system would cycle maybe every 10-15 minutes. Thats just a wild guess at this point though. Most of that time would be the rez and plant buckets slowly filling, followed by a much faster drain.
Edit: I just ran some tests, and with my EchAir commercial pump (2.9 PSI, 793 gph) I can run two of my air stones at full blast and it still pumps at 30 gals/hr of water at the full head height I need. Actually maybe 3"-5" more lift than I need depending on the max fill level in my pots. Im guessing the hydroton will take up at least 1/3rd of the volume in the pots, so I can fill 2ea 5gal pots in roughly 13 minutes at the fastest rate. The drain time should be around 4 times faster, so total cycle time should be in the 16 minute range = 13 minutes to fill and a little over 3 minutes to drain. Does that sound good for ebb/flow system?
are you sure you really want to do dwc/waterfarm type grows as you haven’t got to how much you’re gonna have to reliably depend on ec & ph not to mention nutrient temps I lost 2 waterfarm grows & a homemade dwc with homemade air driven dripper due to high temperatures I’ve done e&f using rockwool,hydroton & my favorite smartpots & coco without a doubt dwc can give some top yields but you gotta be on your game e&f is far more forgiving I still have my waterfarms & remote reservoir but I’m on my second round of dtw in 3 gal smart pots one plant with gh nutes the younger plant with megacrop not trying to discourage dwc by any means but can be unforgiving of simple mistakes
The pump should have a filter that would prevent plant matter getting sucked inside. In my experience salt build up is not a issue with pumps either is plant matter. What will clog a pump is a small piece of hydroton, but again, all hydro pumps have a prefilter. Also, part of hydroponics is maintenance. You should clean your pump at the most every 14 days, so this will also assure the long life of a pump.
I can buy a timer and small pump for less than you can build that system.
depending on the amount of hydroton and the size of the plants, it will not dry out completly for a couple of days. Obviously the larger the plant, the faster it will dry. a 3ft tall plant in 10 liters of hydroton NO REZ will take more than 24hours before it drys. usually 48. also depends on the RH of the room. If you have a double bucket or small rez where the roots can drink, the plants will be fine. If it is too long Dissolved oxygen becomes a problem.
I say one inch is sufficient.
more like 1/2 or more depending on the type of clay pepple size used.
I see you are debating drippers vs Ebb and flow. What I like about ebb and flow is that every time the water cycles and the water drains, it pulls new fresh air into the root zone.
Another idea i had is im going to put a solenoid valve at the bottom of the rez to the controller. Then only need one pump to empty the controller after solenoid closes. Now im just worried if 1" would be big enough of not.
Yeah, those were all reasons I was originally hesitant about trying hydro. Im fairly confident about mixing nutes now, and I have a decent PH/EC/PPM/Temp gauge on order, so I think I can stay on top of all those things as I go forward. Whether or not I will have temp issues with the water in my system remains to be seen, but I am hoping that by not using a submersible pump, I wont have nearly the issues other folks have.
I swear this is the last time I’ll suggest it lol. If temps are in any way a concern check out hempy buckets. You can run them at 80 degrees np. If i was sticking with a small grow I’d def not switch to ebb n flow.
I had not considered much of that info and was unsure about the reliability of magnetic pumps. They were still kind of new lst time I used that type of pump.
As far as cleaning and maintenance, the air lift pump has zero maintenance and cannot plug up with hydroton, or anything else, unless a large piece (in the case of my pump, at least 1/2" diameter) gets to the bottom of the pump - which will be virtually impossible.
I think you would be surprised.
The cheapest water pump I could find on Amazon that has enough head height/pressure as my air pump, is around $15 with free shipping. If you raised the rez high enough, you could get by with a $9 version, so lets go with that one. The cheap, mechanical timers cost around $5. You may or may not also need an extension cord or power strip to reach, but lets eave that out. So lets say you are into it for $15 just the pump and timer.
On my end, I need the air pump parts plus the bell siphon to replace the timer your using.
Every thing else between the two systems will be identical - assuming we both use the same pots, rez, water volume, etc. We both need all the same hoses, uni-seals or bulkheads, fittings, etc to connect up the same tanks and pots, rez etc., to the pump - which ever pump we use.
So, my water pump cost me $5.70. And I can build 3 more for an additional $1.05 in fittings.
Your going to have an over flow drain on your tank, so the only extra parts I need for the bell siphon is the “bell” portion, which is going to cost a max of $5.20. I think I can actually get that down another $1 if I work at it.
So, going with the highest costs on my end Im at around $11.90 max. The electrical pump and timer will be at least $15 minimum. Add in the zero maintenance for the air pump, and it wins for me. Actually, the total cost for either pumping system is pretty small unless you go with a hi end electrical pump and timer, so I think it comes down to mostly personal preference.
Oh, ok. That takes away a huge part of my worries in case of a power outage. Thanks!
perfect
Good to know. Thats one of the main reasons I want to try ebb/flow, but to be honest, its also largely a desire to fiddle around with new toys and getting to unleash my inner tinkerer. If you stop and think about this type of system, its a lot like a Rube Goldberg setup - all that water going in and out and up and down and around corners and automatically siphoning hear and there and then at the end, a plant grows out the top like magic! I love it
