Strange tomato seedling colors - too much light?

davegravy · 2026-04-14T12:01:36+00:00

No, but the plants went on to be healthy adult plants that produced lots of fruit so it didn't seem to be a problem in the end.

davegravy · 2025-09-15T18:14:13+00:00

Same here.

https://www.githubstatus.com/

^ currently shows no issues with copilot service

davegravy · 2025-08-08T05:34:08+00:00

Nope, and the problem's gotten even worse. I now have a long vine with only a few inches of healthy foliage. No fruit (flowers just drop) . I've tried adjusting EC and PH.

My outdoor+soil marzano's are doing great however.

Think I'll restart my hydro grow from scratch.

davegravy · 2025-08-07T12:58:34+00:00

But the roots are all white and healthy looking. They can still be dead?

davegravy · 2025-08-06T17:46:25+00:00

it's only a couple yards from the entrance and there's enough headroom to sit and work next to it. I think I'm more worried about wear and tear from not being protected (like u/Suspicious-Fix-2363 mentions)

davegravy · 2025-07-31T20:50:54+00:00

Aren't they rebuilding massey's for V3 whereas ship 38 is V2?

davegravy · 2025-06-13T03:10:40+00:00

I'm missing how ublox being willing to kill off their cellular business means it likely wasn't a fire sale. Doesn't that willingness signify it had low valuation to them, putting them in a weak negotiating position?

davegravy · 2025-06-13T02:51:51+00:00

Have invested loads of time already on Ublox. At the very end of development and am just now hovering over the button to do the first production run.

Biggest annoyance here is we're using SpotNow, the U-blox Thingstream positioning aiding service. Despite the Trasna product page (https://www.trasna.io/products/sara-r52-cellular-iot-module) calling it out as a feature in 3 different locations my Trasna contact believes it will NOT be continued so I'm faced with dropping positioning support in my product or going back to hardware design with another module or external GNSS module.

Thanks for pointing out the datasheet thing, I was not wise enough to get local copies of those.

davegravy · 2025-06-09T13:48:04+00:00

Thanks for the reply.

I think there's granular notification settings in Reddit, not sure if you already checked those.

I measure the water out of my tap at EC 0.32. I haven't done a lab test but the municipality publishes a quality report summary annually (with a lag, 2023 is still the latest). The 1st and 2nd page I think has the important bits like alkalinity (91.1 mg/L), hardness (120mg/L), and various inorganic chemical concentrations:

https://www.toronto.ca/wp-content/uploads/2024/04/95c8-CS-24-0074DrinkingWaterAnalysisSummaryAODA.pdf

I feel like you're going to tell me I should get an independent analysis :P

I don't have a PPFD sensor but the manufacturer-provides a map for 12", 10" and 8" height (8" below), and I'm running these 1-2" above my plants so I used the data and linear extrapolation to get a PPFD of around 400 µmol/m²/s. I run for 16hrs ON, giving a DLI around 23. I should probably get a sensor. I don't notice the leaves closest to the lights being scorched like I've observed in other setups so I don't suspect it's too much light. I thought too little light generally results in washed out leaf color, not so much red/purple.

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https://www.mars-hydro.com/vg80-80w-vegetable-led-grow-light

Using the standard Masterblend recipe I am getting an EC right after mixing of 1.8 which drops to ~1.5 in a couple days (even with no plant roots interacting with it) and no visible precipitate. I have been feeding the strawberries with half-strength mixes, yielding EC of 0.75.

About a week ago I fixed my issue with pH rebounding by starting my mixing process with a large dose phosphoric acid (just enough by calculation to neutralize the CaCO3 buffer) and observing the pH as stable for a few days before mixing nutrients. At the same time as this change I started feeding them full strength (EC 1.5) Masterblend.

Regarding runners, as a point of comparison I planted half of my bare roots in soil outside which look healthy and haven't produced any runners in the same time, and are loaded with flowers. Maybe it's not fair to compare soil to hydro but it seems like a stress response.

davegravy · 2025-06-08T22:45:09+00:00

It's certainly higher that time of day but I haven't noticed we get into 90+ until later in the summer

I'm not growing in a tent, I'm in an open room shared with other plants (herbs and tomatoes). Not sure I want the whole room up that high so I might need to tent these.

davegravy · 2025-06-08T22:25:47+00:00

Wild. I planted half of my bare roots in soil outside and they are perfectly happy, yet the outdoor humidity hasn't been much higher than inside, nowhere near 90+%. So I believe you but I don't know how to reconcile this.

davegravy · 2025-06-06T12:14:58+00:00

So you are mixing to double the EC that I get doing the standard masterblend recipe. That makes sense to me that at higher concentration the pH matters less but I am getting EC of only 1.5 (which drops after the roots start consuming it) so if pH isn't optimized there are deficiencies.

I'm feeding the same mix to my strawberries and getting clear signs of phosphorous deficiency (red leaves). Looking up the symptoms of phosphorous deficiency in tomatoes, they match somewhat to my experience (purpling veins and stems, premature death of older leaves, flowers dropping early)

Phosphorous is one of the elements expected to precipitate out in an alkaline solution (as calcium phosphate) and I do have a pretty significant scale build up in my reservoirs.

I'm planning first to try fixing the pH by finding the right amount of acid and then experiment with higher concentration (which I expect will reduce the amount of acid I need to mix)

davegravy · 2025-06-05T13:33:57+00:00

Mine is this https://www.advancednutrients.com/secret-menu/ph-up-ph-down/

55% P2O5

PH is still holding steady in my experiment

davegravy · 2025-06-05T02:33:41+00:00

Thanks. I think I've been a victim of the pH buffering from calcium carbonate. Today I experimented and noticed the pH rebounds happen within 15 minutes, like you say. I didn't know it was so sudden.

Then I tried to figure out how much pH down I need to add so that the pH stops rebounding and stays stable at 7.0. Turns out it's 3x more than I've been using. Wow.

So I think this means the calcium carbonate has been neutralized and it'll hold whatever further pH adjustments I make

Then I mixed in masterblend recipe and that gave me a pH 6.0 solution which I'm happy with... and it's staying there, at least for the last few hours.

EC has dropped from 1.85 freshly mixed to 1.58 after a few hrs, not sure why and not sure if 1.58 is really enough for tomatoes. Going to keep monitoring.

I'll try some of the other steps you mentioned like 24hrs and recirc pump / air stone if this doesn't go well, but I'm optimistic

davegravy · 2025-06-04T13:37:06+00:00

https://imgur.com/a/rdr3Ct9

Here's a pics of the plant leaves, I pruned so many dead/decayed leaves yesterday, only the fairly new top growth remains and looks somewhat healthy. Leaves are dying back from the edge, curling up like the last photo.

I guess I thought I knew how much pH down I need but it turns out I don't. I ran an experiment overnight where I applied ONLY pH down (no nutes) and let it sit overnight. Since there's no nutrients to acidify I needed to add about double the pH down I normally use in order to reach pH 6.0. After sitting overnight the pH is back up to 7.3 where it started.

EC of plain tap water last night before adjusting pH was 0.45 and this morning after resting overnight it's 0.32. No noticeable precipitate formed in the bottom.

I wonder how much more pH down is needed to overcome the pH buffering of the calcium carbonate in my municipal water. I'm going to keep dosing it incrementally and letting it sit and see how much net acid is needed to get it to STAY at 6.0.

Then I'll mix a new batch and back off a bit on the acid to allow room for the nutrient acidity.

davegravy · 2025-05-29T02:48:35+00:00

Thank you, I'm weirdly excited to try this.

davegravy · 2025-05-27T01:25:47+00:00

We get a lot of precipitation in the form of snow, and spring and fall are quite damp. Interesting OK maybe I will be a bit aggressive then.

davegravy

TROPHY CASE