I think Tom mentioned that pearling happens when the O2 production by plants exceeds the rate at which it is being dissolve which is why you see pearling on leaf surface. You don't need O2 saturation of the water column for that to happen.

In that case, if you are very sure your CO2 is good, increasing light intensity will increase plant growth (more O2 as a by product of photosynthesis).

Regards,
Peter Gwee

I use Equilibrium to boost the GH, but I use only a little, and only when I find the tap water is no longer at a moderate GH level. Equilibrium isn't extremely cheap, but it is usually available at a LFS. For a big tank like you have, it is much more economical to just dose calcium sulphate or chloride, and magnesium sulfate. As I recall, the GH should be above 5 degrees, and yours is less than one degree, so you could just ignore the natural GH and dose enough to arrive at about 5 degrees. That way you know you have both calcium and magnesium in the water. You could start by dosing about one third as much magnesium sulfate as calcium sulfate or chloride. Neither calcium nor magnesium has to be available at some fixed amount, they both have to be available with about a quarter of the GH made up of magnesium. But, the plants wont be harmed if you overshoot in dosing by a factor of two or more.

Iron is not what gives plants their red color, so you are likely to have enough just by dosing CSM+B. A bit more won't do any harm.

After re-reading all of your posts in this thread, I really don't know why you don't get pearling. I'm guessing that there is something obvious involved, but the only thing I can think of is CO2 - perhaps it leaks before all of it gets to the tank, and perhaps the drop checker isn't being used right.

Hi,
There is no way at 30ppm injection rates that a 10LB CO2 tank will last 6 months dosing a 125G. No Way (sorry ). Try a 40LB bottle. Also, I may have misinterpreted your post but it appears you are modulating the CO2 as a function of tank pH. Is that right? That might be one reason for your BBA which is associated with insufficient and/or fluctuating CO2.

In general, it's probably not a good idea to use a pH controller because they tend to generate large swings in CO2 in order to meet the pH demand. In fact you really shouldn't care about what pH you shut the gas off at. You should only be concerned about what your level of dissolved CO2 is (30ppm) based on your drop checker, and whether this concentration level negatively affects the fish. It sounds like you have very expensive fish so you need to be careful about the injection rate. If the rate is steady they can adjust to it but if the rate bounces around it might be problematic.

Because you have a large tank it's very difficult to get the CO2 right. I have a feeling that you may not have zoomed in on the right injection scheme if you are focused on tank pH. You need to turn on the gas an hour or so before lights on and leave it on until a few hours before lights off. I've got to give UKAPS a plug here so check this article on CO2 measurement: Welcome to the UK Aquatic Plant Society :: View topic - CO2 MEASUREMENT USING A DROP CHECKER

If you are dosing EI in a 125 then I'm assuming you are adding 1.5 teaspoons or so of potassium nitrate and 1/2 teaspoon or so of potassium phosphate 3X per week plus 1/2 teaspoon or so of CSM+B 2X per week right? In a big tank with lots of plants and light you could easily double those numbers with high CO2.

I know you said that you have done a lot of research etc, but the combination of BBA and lack of pearling is a pretty clear indication that there is a discrepancy in NPK and/or CO2.

Adding Flourish Iron if you are already adding CSM would not really be productive. A week is not really enough time to see full recovery. 3 weeks is more likely.

Cheers,

Vaughn - thanks for the advice about the GH. I just retested my GH and it is 5.7 percent. I just checked my test kit and used the % conversion, so I guess I don't need to do anything.

ceg4048 - I think you may have hit my nail on the head. I need more CO2. I finally found 2 leaks and so I think that was my culprit about using my CO2 so fast. I was able to tighten things up and hopefully I have eliminated them. I am going to order another tank so I will have one on hand that is full to avoid spikes.

While I have been using a pH meter to turn my solenoid on and off I have been watching my drop checker. I will keep my drop checker at a more lime green and see what happens. I will keep an eye on my fish. Thanks for the link - I will check it out.

My plants do seem to be flourishing except my marimba balls. I dipped them in the 20:1 water/bleach solution and I guess you can't do that because they look bad. Silly me! I trimmed them and cut off 1/3 of the outside. They are green inside so I hope they will be ok. I still don't have much red in my red plants, but good growth. I am dosing the CSM+B faithfully. I want to make my changes slowly so that I don't over do and have real issues.

My BBA has mostly disappeared except for spots on my anubias nana and another anubias type that I don't know it's name. The latter is actually growing more so I need to dip it and trim it. I am continuing to dose flourish excell and hope with that and more CO2 the BBA will be a thing of the past. I also tested my Nitrate and it was only 5ppm so I re-dosed. I'm sure that is contributing to my BBA issues.

I am coming along with all this stuff. I know more today than I did yesterday. Like Tom Barr had told someone in a recent thread, "it's the newbees that have all these struggles....." The good news is that we aren't newbees forever!!

Thank you so much for your help. I've posted a few pxs of my tank. It's a typical collectoritis tank. I want to see what I can grow best first. I have a theory that you are either a plant collector with a mass of plant varieties or a tank collector with the same amount of plants just in many tanks! My husband says I can't be a tank collector

Just a quick update:

BBA: I left for a trip for 5 days and turned my lighting back to 7 hours. I turned my C02 back also since I would not be here to watch my fish with the lower light/plant growth. I don't see any new BBA. The otos have eaten a lot of what was there. Of course I also wasn't here to add ferts.

Plant Growth: I have had a lot of growth since I left. My aponogetons have almost doubled in leaf height with lots of new leaves as well. My stem plants, of course, have grown a lot and some need a trim. Wisteria doubled. Stargrass doubled. Still don't have a lot of red color in Luwigia repens - just at tops, but growing well. My marimba balls are starting to recover from their bleach dip. Echinodorus Kleiner bar getting big and beautiful dark reddish color. Marsilea has new branches. Vals sending new babies like crazy. Maybe it's just not seeing them every day OR - maybe things are starting to balance out.

Pearling: Still none. I have 2 36" compac with 96 Watt, 6700K fluorescents in them That is 192 watts each = 394 Watts for 125 gal. Do I really need more light? Thinking about having two 4 hour photo periods so as to maximize light length and yet not stimulate any algae growth. What do you think?

CO2: Got another tank so that I will have a spare and will not run out. I will turn it back up since I am home. Hopefully will get some pearling.

!!!DANGER Will Robinson!!!! Adding more light will likely result in more BBA than more pearling. You need to be patient and to keep the eye on the prize. Good plants growth and good health are the objectives. The tank looks healthy and the mass will fill in. Getting hypnotized by bubbles is a less worthy objective although it may seem more thrilling. Breaking up the photoperiod wil only help algae so leave the lights alone - if anything you'd be better served lowering the wattage if anything. Try adding more CO2 instead....

Cheers,

Hate to tell you, but I think you showed your age with that one! There are actually people walking around today that wouldn't have a clue as to who good 'ole Will is!

In the reading I've done it was suggested to do this - that the plants can handle it but the algae can't. Part of the same reasoning, I thought, Tom Bar had given for the 3 day blackout.

I certainly won't sacrifice plant health for pearling so I will stay my course for the time being. I have my CO2 at lime green now so I know I have enough of that. I had a faulty CO2 needle valve and have gotten that replaced. I think that and just beginning to use EI caused my BBA problem originally. Things do seem to be settling down some.

On another note: Got another piece of Manzinita driftwood today. It is so cool. I'm working on finding hardscape pieces so that I can take out that one last fake one I had gotten from Petsmart. It's about 18" wide! My plecos are gonna love it!!!

You know, my tank has been up for about 4 months and I've never really seen heavy pearling until my intake tubing had an air leak. A small stream of bubbles was sucked into the pump and mixed into the water. This had to cause higher o2 levels in my tank water and that afternoon all my plants were pearling like mad. I know my co2 is high and my flow/circulation is too, even the surface movement was decent (I thought) but I never saw pearling. And often my shrimp had problems in the early morning - they were all gathered at the top. But when I added an airstone (or recently additional air with a mazzei) I had extreme pearling on all my plants. I have always had great growth and no algae, I use EI and a drop checker, but never saw pearling until I supplemented areation/oxygenation. Maybe this is cheating and I'm not doing something right, it just seemed that my o2 levels were not high enough. The pearling only occured when I oxygenated, and didn't occur on days that I didn't. I know that pearling shows only when o2 is produced faster than the water around it can absorb it, but this was the only thing I changed on these days and the correlation was obvious. It showed up with the airleak in the tubing, when I used an airstone, and when I added air with my mazzei.
????
I dunno why it doesnt occur without it, but this is my observation on my tank and with my setup.
???Any other thoughts? Am I doing something wrong/missing something?

-Mike B-

How interesting is that! It sure seems counter-intuitive! Supplemental O2 is supposed to drive CO2 out of the water. It's not that the added air bubbles are just being trapped by your leaves, is it?

Haha, you busted me Tex Gal I thought I would just pretend that I saw ole Will on Nikelodeon re-runs...

One analogy that helps me to keep perspective on the plant vs algae response is that of a comparison between a small simple car like a Fiesta versus an exotic car like a Ferrari. The Fiesta is easy to get up and running so responds quickly. The Ferrari is a very complicated machine. Lots of processes going on lot's of parts moving about and very high maintenance. Once it's up and running it can beat the pants off the little Fiesta, but for quick trips, short distances and small spaces the Fiesta wins. Algae is the Fiesta. They easily and quickly respond to changes in the environment so that when you turn the light on they are quick off the mark and can start feeding immediately. Plants, due to their much greater complexity take much longer to spool up. It takes them a while to get going. If you then turn the light off after 4 hours they spool down. Then you turn the light on again a short time later and they have to slowly spool up again. The Fiesta is quick to get out of "Park" and back on the road. When the light goes on they're up and running. If the light goes off for a little bit no problem. When the light goes on again they are back up and running in no time flat.

I figure that the 3 day blackout works to the plants advantage because it's much more long term. The complexity of the plant means that they have more reserves and backup systems to ride out the long blackout. Algae don't have the reserves so extended loss of light causes them to shut down and head for long term parking until the good times return. Same story with CO2. If there is a change in CO2 concentration the plants try to reconfigure their body chemistry to adapt to the change. That may take a week or more, During this time they are inefficient and they suffer. Algae adapt to the CO2 change immediately, again because of their simple construction.

If we want the plants to outperform the algae environmental stability is a key. That means by lights on you should have maximum CO2 so the plants don't have to chug and lug waiting for the CO2 level they are accustomed to. That's a reason we're instructed to turn the CO2 on an hour or more before lights on.

Mike brings up an interesting point about oxygenated water being more likely to have pearling. I'm not really sure but it sounds reasonable. My preference though would be to enforce pearling by producing more oxygen so I reckon more plant mass, more (stable) CO2 and more dosing are the most influential factors. You just have to make very minor adjustments to the needle valve in order to avoid gassing the fish.

Is that just the photograph or is that piece of wood the size of your door??? It looks huge

Cheers,