Easy care setup for present

[MT-Phal]

But isn't the point to increase chances of success for your girlfriend? And for as long as possible? Seems to me that this may work, and it probably won't. From my experience if there isn't decent airflow than the roots and medium tend to grow mold. I have mine right next to an open window and I still get mold on my roots, despite a decent breeze. I do my best to negate this with constant flushing, using hydrogen peroxide, and watering with a physan 20 solution once a week.

If you set this up in your girlfriend's basement, unless you set up some kind of fan, you might be in a situation which harbors fungus/mold. Add in the possibility of the solution mix turning toxic for your roots b/c of lack of proper flushing, and this is possibly a recipe for a dead orchid plant.

I don't mean to be discouraging. And this system may indeed work, but I hope you have a better understanding of this process and how it works for, and possibly against, your plants.

[tokyo]

I understand that this is not an ideal situation. But making a self sufficient system is part of the challenge.

Also, without a self sufficient system I might as well keep the orchid for myself.

So I am determined to get this to work.

If I used a low power aquarium air pump to pump air into the medium would this help with aeration? Or would the direct flow of air damage the roots?

As far as the nutrients toxifying, what if the water reservoir held just water with no nutrients and the nutrients were added to the 1" at the bottom of the system? I would have to figure out the right amount to add so not to end up with too concentrated a mixture, but this would allow nutrients to be used without having them sit for an extended period of time.

The only thing is I'm not sure how important it is to have a constant supply of these nutrients. would it be enough to have nutrients added twice a month? The nutrients would stay in the water for a while and just become more and more diluted as new water was added.

[Undergrounder]

Originally Posted by tokyo

I understand that this is not an ideal situation. But making a self sufficient system is part of the challenge.

Also, without a self sufficient system I might as well keep the orchid for myself.

So I am determined to get this to work.

If I used a low power aquarium air pump to pump air into the medium would this help with aeration? Or would the direct flow of air damage the roots?

As far as the nutrients toxifying, what if the water reservoir held just water with no nutrients and the nutrients were added to the 1" at the bottom of the system? I would have to figure out the right amount to add so not to end up with too concentrated a mixture, but this would allow nutrients to be used without having them sit for an extended period of time.

The only thing is I'm not sure how important it is to have a constant supply of these nutrients. would it be enough to have nutrients added twice a month? The nutrients would stay in the water for a while and just become more and more diluted as new water was added.

IMO forget the extra air idea, the roots won't need any more air than they happily get in LECA. If you use a completely inert medium there will be nothing for mold to grow onto in the first place. Another reason why you have to use LECA.

The problem of nutrient salt buildup is this: The LECA medium wicks up nutrient laden water from the reservoir, which evaporates near the surface. As it evaporates it leaves behind the nutrient salts stuck to the LECA near the top of the pot, which buildup to a level that stops the roots being able to draw up moisture.

You can't get rid of the excess salts unless you flood water back through the LECA medium from above and let it dissolve and drain away the salts.

You can slow salt buildup by either:

1. Limiting the amount of nutrients you use in the first place, or

2. Slowing down the rate of evaporation, ie: with a top dressing of pebbles, limit air flow over the medium, ensure the reservoir never runs dry, etc.

But no matter how fast/slow it builds up, it will build up. And after a period of time the root zone will need to be flushed with fresh, flowing water. I flush my system about once every 6 months, but most people need to do it about once a month. Using Ray's (still the best option) technique, you don't need to worry about flushing because it's incorporated into the weekly watering regime.

[tokyo]

Oh, well flushing once a month isn't a problem at all. I had that worked into the plan already. I was worried that it wouldn't be enough.

I just got a bag of LECA today that I ordered online over the weekend. Its alot more than I need, but its good to have around as I'm sure I will be starting a couple orchids of my own in the not too distant future.

How often do you need to feed nutrients? Do you add them with every watering or do you just do it occassionally, like every other week? I have heard both.

I was thinking if nutrients were added to the 1" pool of water twice a month it should be good enough to keep the orchid healthy.

[MT-Phal]

Mold will grow directly on the roots, particularly the tips. Fungus can develop on the medium itself by the resevoir. I have issues with these on a regular basis, and they've been documented in this forum if you want to look at those threads.

The nutrients are not what become toxic to the roots. As a root takes nutrients in, it also releases a waste by product. If that is not removed, via flushing, the changed chemistry is what is bad for the roots. Again, this covered within the forum and Rays site in better detail. I suggest you browse his articles for a better understanding of how or orchids work, and how they may or may not work in a hydroponic system.

[tokyo]

Ok, well I'm confused now because I am getting two different answers.

MT, you said the air flow in the medium helps prevent mold. Do you think the idea I stated earlier of using a low power air pump to blow air into the medium would help with this? Or maybe just a small fan blowing air over the top of the medium? How often do you think flushing should be done?

I think I will just set it up the way I said and tweak it if I have to. Worse case scenario she will have to do regular flushes of the system, which should only take a few minutes.

Since my planned system is essentially the same as ray's. It's just missing the regular flushes. I don't see any reason not to go ahead and set it up

[Undergrounder]

Originally Posted by tokyo

Ok, well I'm confused now because I am getting two different answers.

MT, you said the air flow in the medium helps prevent mold. Do you think the idea I stated earlier of using a low power air pump to blow air into the medium would help with this? Or maybe just a small fan blowing air over the top of the medium? How often do you think flushing should be done?

I think I will just set it up the way I said and tweak it if I have to. Worse case scenario she will have to do regular flushes of the system, which should only take a few minutes.

Since my planned system is essentially the same as ray's. It's just missing the regular flushes. I don't see any reason not to go ahead and set it up

Don't worry everyone has their own opinions, mine differ from Ray's in a few points because of my own experiences. But salt buildup is very much the primary concern and the reason we 'flush' the media, Ray explains it more here. The buildup of phenols and imbalances in the nutrient solution are a lesser concern and gets fixed when you simply refresh the nutrient solution, without necessarily needing to flush.

If you use too much (any) flowing air in LECA-based hydroponics or S/H you'll only hamper it's ability to wick moisture and you'll only dry it out faster and speed up salt accumulation. You'll decrease humidity around the plant, dry it out faster, need to water more and raise the nutrient's strength dramatically between waterings.

This is a graph of the relative strength of the nutrient solution in one tray of my hydro system. I left the fan on for the first 5 days and refilled the reservoir on the night of the 5th day. For the final 9 days (and forever after that) i left the fan off:



You can see the extra airflow only served to dramatically increase the strength of the nutrient solution above dangerous levels (Ray recommends i think 150 - 250ppm max). I don't recommend additional air-flow if you can avoid it with a S/H system.

Nutrients are an altogether different problem, and you best read up on them at Ray's site or elsewhere, you need to consider the type, strength and pH of the nutrient. But relatively simplified, you just add a very dilute amount with every watering. About 150parts of a balanced fertiliser per million parts of water is about normal. There are calculators to figure out how much fertiliser this is on Ray's website also.

[tokyo]

Alright, I finished it. Heres a few pics.


I used a wicker basket as a background for the plant and to hide the water reservoir.



I used aquarium airline tubing to deliver the water to the pot. One line is to deliver water, the other is to return air to the air tight reservoir. The air return tube controls the water level. There is a plastic strap that holds them in place inside the ceramic pot. The plastic planter can be taken out to flush the LECA and the tubing won't be disturbed.


Here is the plastic bottle I am using as a reservoir. I am going to be replacing it with something a little bit bigger. The rubbermaid container I was originally going to use turned out not to be air tight. So this is a temporary backup.


I'm going to be attaching a thermometer to the basket to help monitor the temperature and make it easier to meet the environmental requirements for the orchid to bloom.

When I repotted the orchid alot of the roots seemed to be dead, but there were also a lot of new roots. opefully it will adjust to the new environment without too much trouble. It was in sphagnum and bark before.

[Undergrounder]

Ingenious tokyo, i love it! Looks great.. Does it get a lot of light? It might need a bit more, i wonder if you could attach a short T5 fluoro with a mirror inside a slim casing attached to the top of the basket?

[tokyo]

I was told that Paph. fairrieanum needs low indirect light. Right now its to the side of a SW facing window. It is also not going to be here permanently. Depending on the condition and lighting of where its going I may need to add a light on a timer. I also may need to add a fan for temp control because the apartment where its going is heated automatically to a set temp, so in the winter it may be a chore getting the Paph down to 50°-60°F at night, which is a requirement for it to bloom.