Missing a Nutrient?

[djlen]

Most of you probably know by know that I'm in a constant battle with the dreaded brown hair algae. I use DIY CO2, and Flourish, Flourish Excel, and Flourish Potassium at the dosages recommended on the bottle. I am getting 0ppm readings when I test for nitrates.....hence the stump remover to add the nitrates.
Something is missing.....when I do my weekly water-change the tanks look like a champagne cocktail and then gradually taper off to just a light pearling as the week goes along. There's something in my water that I want to add during the week to give the plants the opportunity to out compete the algae. I'm thinking it is the nitrates, but I'm so clueless when it comes to this stuff I could use some feedback on this issue.
Len

 

[Tempest]

Could we have a little more information? What size is the tank and how much light? What is the range of kH and pH in your tank with the DIY CO2? Do you think the bottle or bottles is having a problem keeping up the level of CO2? I see you dose potassium and nitrate but how about phosphate? Do you have an idea if you have enough in the tank already?

 

[djlen]

It's a 40 gal. with 110 watts flourescent. The KH is 2.5 - 3 and the PH is 6.8 - 7.0. I monitor my PH daily and the bubble count into the tank. To keep an even flow I replace bottles approx. evey 7 days, there-by maintaining a pretty steady 6.8(15-20 ppm CO2). Phosphates could be a problem. I feed sparingly and am going to pick up a Phosphates test kit. Just started adding Potassium Nitrate to maintain 5ppm.
From what I've read, the plants will out compete the algae for nutrients and thus help reduce the algae if I can get them up to optimum growth. That's why I asked the question originally regarding the pearling right after water changes. The plants pearl to some extent all week, but nothing compared to when I've just done a water change.
Any thoughts?
Len

 

[plantbrain]

A few things:

At the KH you mention, you'll want to keep the pH lower.
Aim for 6.4-6.5 range.
Now check the pH right before the lights go off. What is it?
You need to try and have lots of CO2 during the light period for the whole day, not just in the morning.

PO4/phosphate:
No, try the CO2 and K, and NO3 for algae issues. NO3 and CO2 are the two biggest issues for algae problems.

I add PO4 to about 1.0ppm. I have no algae. Been doing this for 10 years now. So have many others. You might need to add it. Check with a kit to see. Also ask the water company what their reading are for NO3 and PO4.

DIY is rough to keep things going well. You seem willing to work on it and test etc so you will have good luck with a few little tweaks here and there.

Gas tanks make CO2 easy as pie.
Then all that's left are nutrients and pruning etc.

And thats not difficult.

Regards,
Tom Barr

 

[Tempest]

I think I'd be a little concerned that the kH was a bit low for pH stability and try to get it on up to 4. (Not that this is the problem you are asking about) The ph/kh chart I have says that you are low in C02. You are also using Excel though so that probably helps too.

I had a hair/staghorn problem at one point in my tank but I either seemed to outgrow it as the tank matured or my dosing of fertilizers came more in to balance. My tap water was totally deficient of phosphate and I couldn't get enough out of fish food.

 

[djlen]

Tempest, yes I know the KH is low and I've put 2 tbsp. of crushed coral into the filter(in a bag) to try to rectify this as I was getting very low readings PH when I started using DIY CO2 and was alarmed when the chart said I was pushing 30-35ppm CO2. Now, with the same, or about the same(DIY CO2) injection of CO2 my reading is 6.8-7.0 PH which, according to the chart is about 15 ppm. I feel safer for the fish, but question (after reading Tom's comments) whether I need to either take the crushed coral out or push the CO2 with another bottle. I'm now adding Potassium Nitrate so I think I'm addressing Tom's other comment as well.
Phosphates scare me.....I've cut back somewhat on the feeding thinking that might be part of the problem. Not sure of exactly what to do with regard to that.
My plan is to get to the point where I can make a determination as to the right nutrients for the tanks, and also to pick up a regulator(I have the CO2 tank) and go the pressurized route. DIY is OK, but too much fluctuation and uncertainty as to the amount injected.
One other thing....these tanks are relatively "new" set-ups...less than 4 months. I hope things will settle in with time and as Tom puts it "Tweaking". Once I figure out the right amounts on the nutrients I will make up a mixture of PMDD and have at it.
Tom, yes I'm working my butt off on this. I want it to be right. I guess I'm somewhat like your students(you've fooled me into doing the work). Do I get a grade at the end of the semester?
I've got a whole section on my hard drive with your comments and papers in it. I even have a "Tom's Glossary" cause to be honest with you when you start with the K's and NO3's and K2SO4's I'm lost so I go to the "Glossary" to translate what the devil you're talking about.......clueless, I know.
Thanks for the patience and the help.
Len

 

[Tempest]

Len I don't know what chart you are using. Here is the link for the one I use:

http://www.sfbaaps.com/reference/table_01.shtml

It just doesn't show the amount you are reporting so I guess not all charts say the same.

I use DIY myself and it *can* be a pain in the rear to keep on top of. I found that constructing a gravel tube reactor helped a lot. I have a 55 gallon with 2 bottles kept at 80 F in a bucket. I use the *jello* recipe and replace one bottle every four or five days. This seems to keep things pretty even. I can look at the bottle and then tell when to start a new one just from the looks of the jello in the bottle.

Don't be *afraid* of phosphate. You need phosphate in your tank too. You just need to find out how much you have already.