Well something's not right

Fe or N would be my guess. Even though N is typically supposed to affect old growth first, it can definitely cause pale tops.

Just my own experience lack of Fe tends to turn new growth a distinct pale white color, N is more of a pale yellow. Not sure what that is worth just a personal observation.

I would be very suspicious of the current test results. Liquid drop tests for N read notoriously high, and hobby level Fe tests might as well be useless.

Assuming 50% weekly water changes, the most N you could possibly have is 14 ppm, and that's if the plant uptake is zero. Fe levels are in the ballpark, if again there is zero plant uptake. And obviously there should be SOME plant uptake. The lab results should paint a clearer picture

CO2 can cause all these symptoms as well, so you might try bumping it up a bit just to see of anything improves.

Then I would try N > Fe > possibly micros in general. Total speculation of course.

This is very interesting, be sure to update what happens!

The tests are Hanna Checker colorimeters for Fe and PO4 and Lamotte for NO3, so was hoping they're at least in the ball park, but we'll see. I think I enjoy playing with test tubes as much as I do torturing plants. Definitely jealous of portalmaster's toys :smile2:

Water report says Nitrate from the tap is 6 - 20ppm, average of 12. I'm sure that varies seasonally, but putting 6ppm from the tap into Zorfox's calc was giving me a peak of ~20ppm (with 0 uptake, as you say). There was no input in the calc to account for the fish feeding habits of my 3 year old, so thought 10ppm reading passed the reasonableness test - but interpreting even the Lamotte kit is definitely a crapshoot sometimes. Something I'd definitely glossed over so thanks for pointing it out.

I'll keep up with the current routine + Mn for now while I wait for the labs, maybe up the NO3 if things start to look dire. Will definitely post the results.

Thanks burr for your input here and all the great stuff posted in your journal - invaluable stuff!

The tank is a 40B. I have a 36" Finnex Stingray and a 36" Current Satellite + Pro. The + Pro is running at 75% output on all channels. Don't ask how I landed on this setup, I'm not sure either. :smile2: Both lights are sitting right on top of the tank. About 14" on average from lights to substrate. No cover.

I used an Apogee SQ 420 to take the readings in the center of the tank, pushed down into the substrate so that the top of the sensor was level with the substrate. I know that particular model is not calibrated specifically for LEDs and that it cuts off a bit at the upper end of the spectrum - so definitely not 100% confident in the reading.

As a sanity check: CoryWM did a review of the + Pro with the newer model Apogee for LEDs and that picks up the higher end of spectrum. He came up with 75 par at 100% at 10". Inverse square would put that at ~38 at 14", I think. Running mine at 75% so estimate 29 or so from the + Pro. Another CoryWM review on the Finnex site looks to put the Stingray @30 par at 16", so 40 at 14". I guess that could put me around 70.

Sounds like you think if the par really is closer to 45 that it might be lack of light, not a deficiency. If I'm closer to 70?

I think the readings should be just fine. I am measuring with a seneye and I would think the Apogee would be more accurate. But even with a 10% wrong reading it would not really matter for the things we use it for.
Anyways, I have no experience with Finnex stuff but they seem to be rather popular. It sounds like they should be able to give enough light but I really have no idea to be honest. I am just making a reference to my own readings on my tanks. The big tank with my DIY led light has around 150 par 50% dimmed and this feels about "right".
The smaller tank at 110L got two 24W T5HO bulbs and I get a reading at 100-120 par at substrate and around 70 in the very back and front, though I did not push the sensor down into the dirt. That setup should according to the old W/L measurements be a low to medium light setup. I was just thinking that if you only have half that of my par yours would be in a real low light setup. Sounds a bit strange though. Do you have visible pearling from the plants currently?

PortalMasteryRy said:

What type of substrate do you have?

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Regular flourite. Washed and put in with the new tank setup ~11 months ago. 1-3" deep

PortalMasteryRy said:

The color of the tops of the L. aromaticas do look weird but the growth looks healthy. I've seen those the L. aromaticas in tanks with low nitrates and it gets them to show the reddish leaves more.

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The undersides of the leaves do have a bit of red in them even as the tops of the leaves are yellowed

PortalMasteryRy said:

This could be just a case of tweaking a fert or some of the ferts. Also your AR looks healthy so it is a good indicator that you have more of the nutrients available to your plants.

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The AR does seem healthy. Growing at a good clip, putting out side shoots which do well when clipped and replanted. Some of the older leaves do get algae covered, and there's a bit of undulation of leaf edges. Not sure if that's "normal"

PortalMasteryRy said:

Is your K source only from the KNO3 and KH2PO4??

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I add a bit of K2SO4. My daily 0.8ppm of K is from ~0.6ppm KNO3 and ~0.3ppm K2SO4 (negligible amount from KH2PO4).

Fissure said:

Do you have visible pearling from the plants currently?

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Later in the photoperiod (8hrs + 30 ramp up/down), I do see what looks like a small amount of pearling under the glosso leaves, but definitely not anything substantial. I do see a moderate amount of bubbles floating up to the surface late in the photoperiod in general, but I think that is largely gas escaping from necrotic spots on older Buce/stauro leaves.

Thanks so much for all the insightful questions - I'm really grateful to have all of your input!

Of note: I am now seeing disintegrating older growth on the Aromatica. Shot of that and the AR attached.

Just wanted to post some additional detail on the CO2 and my "1 pH drop".

There was a time a number of months ago when I had pretty bad BBA, but I moved to measuring CO2 via pH drop and ended up dramatically increasing my CO2 rate. Since then, BBA has been pretty much non-existent.

Here's what my current ph curve looks like. Measurements are taken from an Atlas Scientific pH kit using the lab grade probe (+- .02) calibrated at 7.00 and 4.00. It's been consistently like this for at least 2 months.

The surface skimmer turns on for a few minutes late in the photoperiod to add some oxygen and keep the pH from dropping any lower, then runs for a while overnight to offgas and add more O2. I do have pretty solid surface ripple across most of the tank from the filter outflow for gas exchange as well.

This is obviously not a 1 ph drop through the entirety of the photoperiod, but i was thinking with 45par (maybe more based on the quick sanity check) that this was sufficient, given very little BBA in the tank these days. Thoughts?

Oh man, even the AR? They're all suffering. I'm going to call this tank Purgatory. :smile2:

The tap water test from way back showed Ca=~34mg/l, Mg=~10 mg/l from the tap, with a total hardness of 129 mg/l as CaCO3. I do 50/50 RO:tap water changes.
My API gH test shows 4-5 dgH / ~70-80 ppm in the tank. So, assuming that Ca:Mg ratio still holds, I'd suspect I have in the neighborhood of 17ppm Ca and 5ppm Mg in the tank.

Feel like I'm in purgatory waiting on these tank lab results.

Having dug up the old labs for the tap, I do note that they show 0.04ppm Copper and 0.05ppm Zinc from the tap. I'd be putting in 0.02ppm Cu and 0.025ppm Zn with my 50/50 WCs. Anyone know if that's a concern?

It's WC day and lab results aren't due back until next week. Need to try something. I'm planning to do the normal 50/50 RO/Tap WC, but will add CaSO4 and MgSO4 to increase the Ca by 8ppm and the Mg by 2ppm - that should give me a 1.5 dGH bump. Will give that few days, then maybe add some additional K if no improvement.

Lab analysis came back. See attachments and a summary of key parameters below.

mg/l
Nitrate 15.4
Phosphate 1.0
Potassium 22.9
Iron 0.23
Calcium 20.8
Magnesium 6.5
Boron 0.08
Manganese <0.005
Copper <0.02
Zinc <0.02
Sodium 25.5
Chloride 46.0
Sulfate 46

Some thoughts:

1) All the macros seem in a good range. N/P/K is 15/1/23 ppm.
2) Ca:Mg amounts and ratio look good: Ca:Mg is ~3:1. gH is around 4.5
3) Fe is good at 0.23
4) Boron seems really high in relation to the other micros. I'm using CSM+B and FeDTPA. I'd think that Manganese should be higher than Boron by ~2.5x given the CSM stated ratios, but Mn is actually undetectable while Boron is at 0.08ppm. I'm adding .015ppm Fe daily (~0.01 from CSM+B and ~0.005 from Fe DPTA) so I'd expect Fe:Boron ratio to be 12:1. Based on the analysis the levels in the tank are only 3:1 Fe:Bo. I suppose it could be coming in from the tap, but the tap analysis (from a few years back, granted) showed Boron as undetectable (<0.05)
5) Chloride seems "high", but I don't really have any reference. Anyone have any idea?
6) My test kits are actually pretty good. The Hanna Iron and Hanna Phosphate Checker readings I took at the same time I took this sample for the lab are pretty much spot on (0.27 Fe and 0.92 PO3). My Nitrate reading from the Lamotte kit was a little high (I guessed 4-5). Even the API gH kit came in range.

The AR is still crinkly and the L. Aromatica is still yellow (with old leaves decayed). Dosing and WC's have been consistent since the sample was taken with the only changes being adding MnSO4 to my micro mix and a one time addition at last WC to bring the gh up to 6.5.

Going to bump up the CO2 and wait to see if anyone has any ideas