Jump to content

Phosphate difficiency?


CT_
 Share

Recommended Posts

This is a 2ish month old anubias gold coin.  I noticed this leaf turning a little yellow.  Is this a phosphate deficiency?  If so, will the color come back if I add phoshpate?

 

Its my shrimp tank with only a dozen or so shrimp so it gets very little commercial food.  kh ~=80, gh ~=150, tds ~=170.  soft [south of] Seattle water with crushed coral and a little easy green.  light I've slowly crept up on about 8hr/day starting from 4. 

 

PXL_20220410_235415992_MP.jpg.2d1bcd3e7c122a90b2e670497ba87341.jpg

Link to comment
Share on other sites

thats so weird.  this chart shows something totally different for phosphate.  In either case my Nitrate is around 40 (i think from root tabs mostly) so I think I can rule that out.

I wonder what @Seattle_Aquarist thinks about both my plant and the discrepancy in these info-graphics. 

9vk0883bcc701.jpg

Link to comment
Share on other sites

On 4/11/2022 at 3:30 PM, Seattle_Aquarist said:

Hi @CT_
 


I bet your pH is above 7.0.....am I right? -Roy

 

My tap is 8.0+ ph  but like 20-30 tds and maybe 1-2dKH.  I've never seen it fall below 7 even in my other tank with co2. 

 

Just double checked.  for sure >7.2 on the API test.  Honestly pH high test I can't see the difference between 7.4 and 8.0 my coop strips don't read ph right, and i broke my digital meter 😮 .  but yeah 100% its over 7. 

 

Are you suspecting iron?  I have seachem fluorite red substrate, which I think has lots of iron, but I don't think the anubias roots are touching it and I have no idea how much goes into the water column.

Link to comment
Share on other sites

Hi @CT_

It's not that there may not be sufficient iron being dosed or even in the substrate, it is the type of iron that is present that is the likely problem.  Easy Green uses EDTA chelated iron in the mix.  EDTA iron is fine if the pH is below about 6.2 because it is easy to break the bond between the EDTA chelate molecule and the iron molecule which makes the iron available to the plants.  Unfortunately as the as the pH increases above 6.2 the bond becomes more and more difficult to break between the chelate and the iron molecules and the amount of iron available to the plants becomes less and less.  By the time get to pH@7.2 only about 6 we get to pH 7.2 only about 6% - 7% of the iron in the mix is available to the plants.  (See chart for EDTA).  This results in about 93% of the iron in the mix being 'wasted'. 

Normally I would recommend a product like Seachem Flourish Iron which is made from ferrous gluconate but it has it's limits as well as does the other more common iron chelate type DTPA but it will have issues if you are really at pH 8.0.

I live here in Seattle as well and we have great water with it coming out of the tap at pH@7.0 (degassed 24 hours), <1.0 dKh and <3.0 dGH.  I know you are trying to add calcium to the tank for your shrimp but crushed coral is not the one I would use if I wanted to grow healthy plants in my tank.  Coral (also shell, limestone, cuttlebone, etc) are all forms of calcium carbonate.  They dissolve in water increasing the carbonates (which increases the pH) and adding calcium to the water.  I add calcium to my tanks because without it with our soft water I end up with calcium deficiencies.  I also add magnesium for that same reason.  I use calcium sulfate to increase the amount of calcium in my tanks without having any effect on pH (dKH).  If I need to increase my pH (dKH) I add baking soda.  My plants thrive and I have to issues with extremely high pH.

Shrimp do not like major water changes but 10% weekly is typically tolerated without issues.  Doing regular water changes will help to lower the pH in your tank but it will always try to climb as long as the crushed coral is in the tank.

I've had more issues with members on the forum experiencing iron issues than on any of the other three forums I am on combined - almost every one has been related to using some type of calcium carbonate in the planted tanks.  Here are several of them.  Hope this helps! -Roy

https://forum.aquariumcoop.com/search/?q=EDTA Iron&quick=1


911730415_FloridaIronChelatesLg.jpg.01e56b9ad23afec5ec4646e51057cb65.jpg
 

  • Thanks 1
Link to comment
Share on other sites

Thanks Roy!!  I did some digging around and I haven't been able to find an eddha iron product.  though I can see I can buy 10 life time supplies of it as a powder.  Some company named Glosso makes a 1% dtpa iron.  At ph8 thats only 25% available on your chart but 25% >> 1%. 

 

Do you have a recommendation on an EDDHA iron source?

 

Edit: Also since I put it in my mini-HOB the coral should be fairly easy to take out.  I'll go back to equilibrium for my GH. 

Edited by CT_
Link to comment
Share on other sites

Hi @CT_

Here is what I suggest, start doing 10% weekly water changes to avoid extreme concentrations of calcium carbonate.
Start dosing Seachem Flourish Iron once a week per the dose on the bottle.
Watch new leaves as they emerge, do not watch existing leaves they will not change and may continue to decline.
Do the new leaves look greener? Healthier?  Then you found a product that works.  If no improvement then the issue is either not iron related (next most likely is nitrogen) or we have to go to a different iron.

I know you are concerned about your shrimp but dose at least 1/2 the recommended amount of Easy Green twice a week.  Shrimp are much more tolerate than some people think.  You should see what conditions their ancestors (i.e. wild forms) live in where they are wild. -Roy
 

  • Thanks 1
Link to comment
Share on other sites

Yeah I'm actually adding crushed сoral more as an insurance policy against a pH crash.  I'm not really wed to it though.  I'm going to order the sera pH kit which looks easier to read and just keep an eye on it instead.

 

Edited by CT_
  • Like 1
Link to comment
Share on other sites

Well I found the problem.  It was actually anubias rot.

It spread from the nana petite I bought about a month ago to this one.  I'm pretty heart broken because this is the centerpiece plant in the tank and It looked so good.  😞

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...