[EDGE]

I notice when I increase the co2, NPK, and micro in my tank, the plants started to show sign of Ca deficiency.
gH 4

When I kept the NPK, CO2 lean, the leaves did not show sign of any Ca deficiency. The growth was slower, but plants look a lot healthier.

Question is, What is the reasoning behind this? Is K affecting the Ca uptake or is there not enough boron in the water? The source of boron comes from micro mix and flourish (follow up in the plantex + boric acid post). I have increase the micro dose to 10 ml a day. Do I need to increase it farther?

 

[MiamiAG]

EDGE,

The impact of K on Ca and other nutrients, or vice versa, is an area of great debate currently. There is a lot of confusion as to the interaction in an aquarium context.

Can you describe the deficiency you are seeing?

 

[Steve Pituch]

I think it has to do with limiting an important nutrient. Plants need all essential nutrients to grow well and quickly. If an important nutrient is missing the plants cannot grow much at all and very few nutrients are used (growth is almost stopped sometimes). As soon as a missing nutrient is supplied, the missing piece of the puzzle is found, and growth processes resume, utilizing all the nutrients. So when the plant had everything it needed it started consuming Ca like crazy.

So I think its not so much that an excess of some nutrients block use of another, but rather the availability of all nutrients stimulate larger intake and then when all the available Ca is used up you get a dificiency.

How much light to you have and what size is your tank?

The GH of 4 might be a little low. My GH is off the scale at >20 (very hard water), but then the plants grow nicely. You may have to add Ca is in CaCO3, or reduce the light a bit.

Steve Pituch

 

[EDGE]

Burnt/small growing point. This seem to be happeneing to Hemianthus micranthemoides and L inclinata only. They are next to each other.
I put a flourish and Fe tab in the substrate around the plants a few weeks ago.

It is on 4x 55 PC over 75 G.

I can't go extremely high gH with discus in the tank.

 

[Steve Pituch]

Edge,

How much do you know about Discus? I don't know much, but I hear they do well in hard water as long as you don't need to breed them. My friend has one and I think his water is the same as mine, (GH>20, KH=6.5). Don't neccessarily believe what someone tells you at the local tropical fish store. But this would be interesting as many of the people on this forum are more into fish, and this might help solve the perceived fish/plant compatibilty problems some people fear.

I think Phil Edwards has done a lot with Discus and plants.

Steve Pituch

 

[EDGE]

I know enough to have sucessfully bred them.

Aside from the discus and the extreme hard water issue, the city I am living in now has really soft water; 0 gH and 0 kH.

There are some plants I am keeping that require soft water. If I go too high, they might die on me.

 

[Steve Pituch]

Edge,

I looked at the picture in your gallery. Beautiful tank. You are far ahead of me in keeping plants. Now, I don't know whether having soft water is a blessing or a curse. Most of my plants and fish are taken locally. I would like to start keeping and learning how to grow the prettier exotic plants. As a start I will probably guadually convert my 75 gallon tank over to crypts. However, the hard water I have shouldn't be a problem with them.

There is a difference between alkalinity and hardness. Would just adding a calcium compound other than calcium carbonate be just as bad for the discus? I mean it (the Ca) is going to the plants. The other thing is to determine whether cutting back on the light will reduce the need for Ca.

Is the hardness (GH) actually decreasing? If the GH stays constant at 4, I would thiink the Ca is still there (unless it was originally all Mg). If it goes down, what about just adding CaCl2 or CaSO4 to make make the water go back to GH=4?

Just some thoughts from someone who has never had soft water.

Steve Pituch

 

[Phil Edwards]

Edge,

My water is just like yours out of the tap and I've started adding 1/8 teaspoon of CaCl (Kent Turbo-Calcium) to my tank every few days and it's meant the difference to my plants. The discus seem to appreciate it more too.

Best,
Phil

 

[EDGE]

Thanks for the comment on the tank.
That is the old layout before I had to tear it down to replace the tank.

The dolomite I was using didn't had much affect on the gH and kH. It was almost useless in the tank. The testkit would read 0 when I used it. It took way too long for it to dissolve in the tank.

I have switched over to crush corals to increase gH and kH. I am noticing a much faster result with it. It raise gH and kH to 3 in 3 days.

Jay recent post on Ca uptake is worth reading. He has solve the mystery of Ca uptake.

The tank didn't show sign of Ca deficiency when I was running co2 really lean. With low CO2, the plant growth slow down thus consume less NPK and micro. The Ca in the water was enough to support the slow growth. but when I turn up the co2 and all other nutrients, the plant start to stunt from low Ca (at least in my tank).

I am going to let the gH go up to 6-8 for a few weeks and see how the plants grow at that level. most of the gH will be coming from Ca. I will be adding Mg in the form of micro nutrient by dosing it daily.

I am keeping the water at 6.8-6.9 pH now. With kH rising, low pH would result in poisonness level of co2.

 

[Steve Pituch]

Edge,

Sounds like a good plan. I know for my tanks at KH=6.5, and pH=6.9 the CO2 is OK at 25 ppm.

Steve