Machine feeds

[Ca++]

Any experience with feeds that don't need shaking? Or that do?
I know a few people have used auto dosing kit, and wondered how they went about shaking the bottles, or not. I did once have a feed that said it couldn't be machined. I know the ionic range are not happy, as they use black gunk, that will settle. I chucked in a pump, and it was like a gunk magnet. I'm sure other people have experiences to share. Floranova is gritty, for instance. So too abrasive for many delivery systems.


I have been looking at 2L pop bottles. Making a stand, to have them inverted. Then swapping the cap (which is now pointing down) for one from a smaller bottle designed to drink from. The one's with a nipple that can usually be resealed. This nipple could offer a hose attachment point, for an external pump to send the feed back to the top of the bottle. Get is swirling a little, and the bottles shape should see everything make it's way back to the pump. It's my best idea yet, but I feel there must be others that work for people.


I;m also wondering about tank change intervals. I know some feeds may not actually need one. Others may get a bit toxic, topping up elements that might not of been used. I know the standard advice is two weeks, but there is work towards just replacing what is needed being done. I just don't see the full figures.

 

[Orange's Greenhouse]

The usual salt fertilizers (Jacks, Hakaphos etc.) dont need agitation. You dissolve fully (stock solutions of 10 % or more are possible). Sometimes they have a bit of residue but that can be filtered or ignored and cleaned out when the reservoir is scrubbed.

With organic fertilizers you won't get solutions. They are all particles that get broken down by microbes. If they were dissolved it would be salt.

Recirculating systems are difficult. Some elements such as nitrate and phosphate are fully absorbed very quickly while calcium is absorbed much slower and accumulates. If you replenish with the same solution every time it can become toxic. Adjusting pH also adds significant amounts of a specific nutrient.
It's simpler to change out the reservoir every now and then. Measuring the elements and only replenishing what is required is too expensive unless you run 10.000+ plants.
I attached a review article that gives a good description of the topic. If you want to tinker that would be fun and engage you a few years.

 

[Douglas.Curtis]

Air lines are excellent at agitation

 

[Ca++]

@Orange's Greenhouse
I'm topping up my F&D each day, after 20% has been used. It's strange to think a tank change will mean 5x more N P K will likely be available that day. It's never been a problem before. Learning can be dangerous
I'm in a high calcium area, so that might be the guiding reason I should do a change.

Thanks for the reply, it was useful.
www.actahort.org is new to me. I'm looking for the PDF there now, to get an alternate file type.

@Douglas.Curtis
The airline is quite easy isn't it. That could be useful. I guess a bottle tipped to get one corner lower, could be enough with many feeds. I'm really fond of ionic though, with it's simple 'one bottle' for grow, and one for bloom, approach. It's fully chelated though, with humic products. These cause suspension issues.
If Orange Greenhouse is totally on the money, then an airstone would be ample. I have little pumps that fit through the neck of 5L bottle tops. Actually shaped for the job. So it seems a purely salt feed, would easily stay as a solution. I know the shop has to turn the bottles they stock periodically. Which says the manufacturers are not convinced about them standing around. It's some years since I had a bottle stood long enough to get gritty though. Making slushy noises as you swilled it.

I don't quite feel settled yet. It would be nice to hear of a manufacturer, saying their liquid feeds are okay to stand about.
I can't get a reasonable powder unfortunately.

 

[Douglas.Curtis]

I used GH Flora line and Maxibloom dry powder for over 15 years. I assure you, they'll stay in suspension for months in a res without issues. I don't dump my rez till the end of flower and ran mostly DWC. Bottles of Flora will sit around for a few years without issues, and Maxibloom lasts nearly forever when kept dry.

 

[Ca++]

I have something to think over then.
Using 1part, I can dose the tank as easy as chucking a pump, attached to a dripper over the tank. The flow just needs to be slow, as the electronics will decide when enough is enough.
If I use 2part, the A&B need to be dosed more accurately. For me, that would mean two peristaltic pump heads. About £30 a piece. They can share a driver though, which I can do for about £15. I have spare set anyway, as I use one for the acid. I could perhaps water down the acid. They dose that with the pump and dripper. Giving me two peristaltic sets spare.

I'm going to get on them fake dosatrons when I can. Which is another reason I'm on this topic. In an A&B situation, I can likely stick my nitric in the A (having checked the vendors idea of what A should be). Saving a pump, and making full drip supply automation, a $200 job. I have actually mixed nitric with my 1part, stood it 6 months, then used it just fine. It's not beyond reason, but needs another look. A fake dosatron is $50 and the rest I have. It's good having spares around me, and I don't build panels anymore. I do all I can as modules, having learnt everything should be repurposed one day. Though lets be honest, it is great to make a panel that does everything, just because it's impressive.

 

[Hiddenjems]

A stock solution of 1lb of powder per gallon of water works ok with gh Florapro powders.

Gh flora liquids never clog anything ever. But the powders are 5-10x cheaper.

 

[Ca++]

I tried the GH Floranova stuff. It's white clay based, and full of grit. I struggled for a while before noticing the charts give an N expectation, over double what the bottle says it contains. A couple of emails back and forth, and that's me done with them. What they call a guaranteed analysis on the bottle, is a guaranteed minimum analysis when you talk to them. Which they quite rudely said was wrote on the bottle. I dropped the conversation at that. They are struck off.

@Orange's Greenhouse I think I found the document. Bugbee is 2004. It says I need some potassium nitrate, and can about get away with the rest. My zinc will rise, but I like a bit more, as I'm often short and papers on it suggest we should use more. I need to look harder at Mo a know a number of people who just top up, and at least one is a growing super hero.
My N concern with a fresh tank (from reading too much) is quite well addressed there. Telling me the top-up should have double the N of the res. The K almost double. No more P though. Making the Potasium Nitrate look like it could be a rough fit. 13% N and 38% K. A bad balance, but the right things. The K should be helpful, antagonising my climbing Ca levels. I'm really selling this to myself. I think I could need it more than I know.

 

[Orange's Greenhouse]

What they call a guaranteed analysis on the bottle, is a guaranteed minimum analysis

That's correct. They guarantee that atleast this much is in the bottle. All fertilizers are labeled this way. The idea being that the customer needs assurance that certain components, especially trace elements, are present and the company won't put more in than they write on the label.
But this also led to snake oil with "improved delivery technology" where a "low" P fert with just 6 on the label is as efficient as a 18 label. Because they write 6 and put 18 in...
You can't use the label if you want to fine tune your fert program. You have to either make everything from scratch (labour intensive) or send it in for analysis (repeatedly, expensive).

I don't think you can mix acid and A fert in the same bottle. Because drifting pH is Independent of top up. Even without a pH probe you can learn how your plants/res reacts and dose x ml per day of acid (accounting for plant size etc.) and prevent major drifts. Then readjusting manually.

Where do you live? You can get good salts that are more horticulture oriented and less cannabis/home gardener specific. I can recommend some in europe.

 

[Ca++]

I'm in the UK, but not really interested in powdered feeds. I have used the same liquid for decades, and selected my plants using it. It's just too easy, except selecting the kit to automate it. I would look at other bottles, but for powder it's megacrop UK, and they consistently have no stock. They will get me a whole pallet shipped though.

My feed comes as a hard water variant, where they use more nitric in the formula. It's what put me onto the idea. As I say, it's one bottle, and I have put the acid in a few times, and done a long term settling test.
I have not looked up how calnit is made, but suspect using nitric acid on calcium carbonate.

My last dosing system relied on knowing the daily acid use, like you say, you learn to guess. In that system, My drip system ran on a timer, so used the same amount of water each time. The tank filled to a float. So took the same each time. So peristaltic pumps were set on timers, to deliver the same amount. If ran well, but every few weeks I would be changing the timers a little. Many fish tank dosing kits are no different. Just the pipes in them need changing, for suitably resistant one's.

 

[Orange's Greenhouse]

You can turn the powder into concentrated stock solutions. Then its easy to dose/weigh, dissolution is already done etc.
But if you have something that works with your water it won't get better than that.

Calcium nitrate is a byproduct of phosphoric acid production. Calcium phosphate is dissolved with a strong acid. Sulfuric acid is cheap but calcium sulfate (gypsum) is not worth much, so waste disposal is expensive. Nitric acid is expensive but the calcium nitrate byproduct is sold for profit. For cost reasons nitric acid with an impurity of ammonia is used and that results in calcium ammonium nitrate (14.4 % nitrate nitrogen, 1.1 % ammonical nitrogen).

 

[Ca++]

Sounds like calnit and nitric will be fine then. Technically, and proven practically. Though using your feed to set the pH, means only a limited range of EC values can be used. The more feed you add, the more acidic it gets. It's a cheap hack to get one feed injector doing everything. Just for a week or two's holiday. It's probably best left there though, as a sideline topic, for those just wanting a cheap fix.

 

[Ca++]

Although the top-up link was a side note on this thread, My mind has hooked onto it more than my more immediate mixing problem. In fact, I'm now adding more K ppm at top-up, than when making the full tank to begin with. My potassium nitrate has been ordered, and I'm feeling like this could be a breakthrough for me. What I have been doing until now is illogical, and things like them having their best day on tank change day, is a sure sign my top ups have been leading me from the path.

I'm seeing a picture where a new (recirculating) tank is just right. Then the plants drain the N and K faster than everything else. So I come to top up, and must add more N and K than everything else. Or they are no longer present at new tank levels.

It's quite simple really. I always new tank change day with a food fest for them, but this link tells us just which jelly and ice-cream is most popular.

It really is N and K signs I see most regularly, so I believe this is the right course of action for me. It's nice they come together, as the ionic balance +/- is kept. I could just bump total EC instead, but I don't really need everything else increasing. Though my main issue is K, as my water hardness from tap calcium, increases with every top-up. It's been more Ca and less K, every time I top up. It's not a winning combination.

 

[Ca++]

Tomato's but I don't see there being a huge difference. I'm playing on the safe side though, and going with about a 50% increase in top-up N and K

Potassium Nitrate is about 13-0-37 elemental. About my bloom feeds ratio, but 10x stronger.

 

[Ca++]

Well that went well, while my plants were eating and drinking at the same rate. 10 days into 12/12 and that changes though. The tank EC starts to creep up. The amount of feed added to the top-up, can be as low as nothing. I'm going to hazard a guess, that feed use has halved, and a reduction is a normal thing to see.

Everyone think it's normal?

Why is that? Looking at the plants growth, it seems illogical. I'm starting to wonder if the plants decreased Ca uptake is why I retain a high EC figure. Ca is responsible for a lot of the EC reading. I know it's use drop in bloom, but just when, I can't say. Perhaps this is what I am seeing.
If that were so, then the lower amount of feed I'm adding, probably shouldn't lead to a low amount of the N-K boost. It's a science I can't just guess at though. I'm back on F&D pebbles after decades of dripping, so basically I'm a newbie again, needing to just do a bottle grow, as a new benchmark. I need that benchmark, before I can really assess any changes. Even this N-K thing is a bit suspect, as I have no side by side. I have no LED pebble grows in my past. They really did Bolt though. I have had to scissor off some main heads, as they just passed the lights. ffs. Newbie. Lazy fucking newbie, at that.

 

[Douglas.Curtis]

Using Maxibloom powder, I personally find transpiration increases from day one of flower till physical flower bulking quits. At this point I use a drastic reduction in EC to maintain nearly the same transpiration rate as during peak flower.

If anything, my errors are always on the underfeeding side.

 

[Ca++]

Using Maxibloom powder, I personally find transpiration increases from day one of flower till physical flower bulking quits. At this point I use a drastic reduction in EC to maintain nearly the same transpiration rate as during peak flower.

If anything, my errors are always on the underfeeding side.

From day 1? I will have to check my logs. I had forgot the formation of flowers is accompanied by greater water use, but had not really put a date to it. Though at the very first sign of hairs, and I recently learnt it's not actually the flowers doing it. They run hot, as they don't transpire as well as the leaves.
I think you nailed that one. More water use, rather than less feed taken from it. Or maybe both, as it doesn't quite weigh up, from my tank observations. The greater water use, may even tie in with the less efficient Ca uptake. Like a counter-measure.
Good to hear you are reducing feed inputs, although I didn't exact an actual EC reduction. I was at 3, and using it at a balanced rate. Now it's creeping, it could easily be on 3.5 (checks phone, it's 3.66, a new high score)

 

[Ca++]

I carried on the N-K boost, despite having no experience to truly gauge it's use. I actually got more involved.
I figured the N&K dosing, wasn't to correct what I just gave, it's to correct what was in the tank before top-up. That much is clear enough to act upon I reckon.
This means, that even though I watered the tank down (by a full days worth of water) the need to correct the existing feed still exists. Maybe it's a little bold, but I used the N&K, at half the dose a day needs. Even though the days worth of feed wasn't added, to the days worth of water.

 

[Douglas.Curtis]

Thinking about it we have very different styles, not sure I can help. 3EC? Must be a lot of Ca since I very rarely hit half that...

I use a full pH swing to extract the max nutes from a low EC rez, with no changeouts till just before harvest. As EC goes up your transpiration will go down. A 1k hps 4x4 dwc at peak flower bulking uses almost 5 gal a day of un-pH'd r/o water for top offs.(Edit: High mnt conditions though, so 65-70F and 30'ish RH.)