The Planted Tank Forum banner
1 - 18 of 18 Posts

·
Registered
Joined
·
24 Posts
Discussion Starter · #1 ·
Hi, this is my first post here. My HC keep melting after 4 days. I have killed 3 pots so far. Anyone know what's wrong? I just bought the 4th pot and after this one i'm giving up!


75G
21" tall
Flourite
82F
220W GE 9325K tubes
CO2 4-5 BPS
PMDD 2ml/day

Fish: 2 Bala sharks, 4 Minor Tera, 5 Octo, 4 Siamensis, 1 Pleco, 15 Neon Tetra, 9 Ghost Shrimps, 5 Redline Tetra.

I tried adding another light strip 110W (50/50) for a total of 330W but that didn't help.

Yesterday I rearranged the filter outtake to be closer to the area planted with HC, added a powerhead and started dosing Flourish Excel and reduced room temperature to 77F (tank temp is 78F). I didn't notice any significant melting today but it's been only 2 days with this 4th pot of HC. Any advice would be appreciated.
 

·
Super Moderator
Joined
·
12,014 Posts
There really isn't a need to use Excel if you have CO2, as they are redundant.

Why are you still using PMDD? It is quite an outdated method of dosing. With that kind of lighting, your plants are requiring a lot more nutrients than you can supply with 2 mL of PMDD a day.
 

·
Registered
Joined
·
2,328 Posts
is it melting or disappearing? Could your pleco be eating it? How many hours a day do your lights run?
 

·
Registered
Joined
·
206 Posts
HC has very delicate stems, it's possible your planting method may have damaged it as well as flourite being difficult to "push" stems into. With flourite I seem to have better luck covering stems of HC with substrate instead of using tweezers or fingers.
 

·
Registered
Joined
·
24 Posts
Discussion Starter · #5 ·
darkblade, on the bottle of FLourish Excel it says you can use both. i think i have read somewhere that people have been using both to boost growth. i have a big bottle of PMDD and i don't want to throw it away. would it be safe to increase the dose? like 5ml/day?
Robert H, they are melting not disappearing. Light is on for 10-12 hours/day.
leaf, yes there are damanged stems but most aren't.
 

·
Super Moderator
Joined
·
12,014 Posts
Of course on the bottle of Excel it will say you can use both, Seachem wants you to use up their product so that you will go out and buy more ;)

There really isn't a need for Excel if you are maintaining 30 ppm of CO2. The only other benefit of using Excel would be to spot treat algae, if it were to come up.

I don't know what formulation your PMDD is (unless it is based on the old Sears and Collins formula from years ago), so I can't recommend whether increasing the dosage by 3 mL will be effective or not.

Your lights are on for a bit long as well. I would cut it down to 8-10, maximum.
 

·
Registered
Joined
·
2,328 Posts
I would say to try increasing your C02 level, but 4 or 5 bubbles per second seems pretty high already. Some very thin plants have been known to melt from Excel, I don't know if HC is one of them.

You should understand though that plants need time to acclimate before they start growing, and until they get acclimated they often partially melt. Four days is not a long time. It might take a week or two before you see any signs of growth.

What exactly do you mean by PMDD? There is no brand or product by that name. Its Poor Mans Daily Drops, based on the Sears and Conlin paper, and fertilization method-routine that was real popular before Tom Barrs EI came along. It was based on limiting phosphate. There have been a few hobbyists that made stock solutions and sold them. Is that what you have?

I don't think the fertilization matters much at this point because the HC will not use ANY ferts until it is acclimated and growing. Cutting the light period back will not make it grow either. Cutting it back by an hour or two might possibly make a difference in algae growth temporarily, but it doesn't sound as if algae is an issue for you.


You say 10 to 12... isn't it on a timer so it is exactly the same amount of time each day? What are some other possible factors? What other plants are in the tank? How long has the tank been running? Have you been adding any thing else to the water, medications, algacides, anything?
 

·
Registered
Joined
·
24 Posts
Discussion Starter · #8 ·
What exactly do you mean by PMDD? There is no brand or product by that name. Its Poor Mans Daily Drops, based on the Sears and Conlin paper, and fertilization method-routine that was real popular before Tom Barrs EI came along. It was based on limiting phosphate. There have been a few hobbyists that made stock solutions and sold them. Is that what you have?

You say 10 to 12... isn't it on a timer so it is exactly the same amount of time each day? What are some other possible factors? What other plants are in the tank? How long has the tank been running? Have you been adding any thing else to the water, medications, algacides, anything?
yes that's what i have. i ordered mine from aquariumplants.com. i ordered the power mix but they ran out so they gave me 900ml of the already mixed solution.

i have a timer but i'm still working on the tank so some days the lights are on for more than 10 hours. not a lot of plants in the tank, 1 pot of dwarf hairgrass, 1 pot of java fern and 1 pot of java moss. they are all growing fine with the exception of some java fern leaves. their tips look "melted" especially those that get the most amount of light. my guess is that they had too much light? (some days i added another strip light to make it 330W total). the tank has been running for 3 weeks but it is fully cycled. i used the filter and sand from an old tank. i put a small some PaziPro in the tank a couple weeks back when i still had the Discus in there but i have been doing water changes almost daily (because i notice that HC will usually bubble when i do a large water change so i think it would be good to do it daily, at least until HC start to grow).
 

·
Banned
Joined
·
5,009 Posts
- Many people "dry start" HC and then flood it or move it to an aquarium. They find it more successful this way. There is a thread about it. I believe Barr started it.

- You may be better off buying some that has been growing submersed. It is sometimes available in the SnS. Most of the HC in pots has been grown emersed.

- I've melted every pot that I've tried too. It was all grown emersed when I got it.

- You can get some KH2PO4 and dose separately. You can't mix it with your PMDD since it has CSM+B in it.

- Also, you can use Seachem's Flourish Phosphorus to supply phosphate.
 

·
Super Moderator
Joined
·
12,014 Posts
yes that's what i have. i ordered mine from aquariumplants.com. i ordered the power mix but they ran out so they gave me 900ml of the already mixed solution.
Pre-mixed formulas should not be used. You don't know what is it it, and you cannot tailor it to your needs (i.e. what if your plants need more phosphates, which PMDD does not provide?)

i have a timer but i'm still working on the tank so some days the lights are on for more than 10 hours. not a lot of plants in the tank, 1 pot of dwarf hairgrass, 1 pot of java fern and 1 pot of java moss.
That is a lot of light, with a long lighting duration for a very lightly planted tank. I would strongly recommend cutting down on the lighting duration, unless youw ant to grow an algae farm :D

they are all growing fine with the exception of some java fern leaves. their tips look "melted" especially those that get the most amount of light. my guess is that they had too much light? (some days i added another strip light to make it 330W total).
This is normal for Java Fern. Their tips appear translucent as they are growing.
 

·
Registered
Joined
·
24 Posts
Discussion Starter · #11 ·
- Many people "dry start" HC and then flood it or move it to an aquarium. They find it more successful this way. There is a thread about it. I believe Barr started it.

- You may be better off buying some that has been growing submersed. It is sometimes available in the SnS. Most of the HC in pots has been grown emersed.

- I've melted every pot that I've tried too. It was all grown emersed when I got it.

- You can get some KH2PO4 and dose separately. You can't mix it with your PMDD since it has CSM+B in it.

- Also, you can use Seachem's Flourish Phosphorus to supply phosphate.
Seachem Phosphorus is an alternative, not an addition am I correct?
would it be OK to add Iron on top of these two things? if needed?
 

·
Registered
Joined
·
24 Posts
Discussion Starter · #12 ·
Pre-mixed formulas should not be used. You don't know what is it it, and you cannot tailor it to your needs (i.e. what if your plants need more phosphates, which PMDD does not provide?)


That is a lot of light, with a long lighting duration for a very lightly planted tank. I would strongly recommend cutting down on the lighting duration, unless youw ant to grow an algae farm :D


This is normal for Java Fern. Their tips appear translucent as they are growing.
you are right i didn't know about the EI method before making the purchase. i think they follow the typical formula below so i'm going to try to adding KH2PO4 separately as suggested by Left C and see how it'll work out.

http://www.thekrib.com/Plants/Fertilizer/pmdd-tim.html
1/2 Liter solution of Poor Man Dupla's Drops:
1 tablespoon chelated trace mix
1 tablespoon MgSO4+7H2O
2 tablespoons K2SO4
1 tablespoon KNO3 (varies, depends on your nitrate)

this is quite a huge increase in the amount so it is a bit scary:

http://www.barrreport.com/articles/42-ei-light-those-less-techy-folks.html
60 – 80 Gallon Aquariums
+/- 3/4 tsp KN03 3x a week
+/- 3/16 tsp KH2P04 3x a week
+/- 1/4 tsp K2S04 3x a week
+/- ¼ tsp (15ml) Trace 3x a week
50% weekly water change

3/4 tsp of K2SO4 and 3/4 tsp of Trace a week would translate to 9ml of PMDP a day if my math is correct.:eek:
 

·
Banned
Joined
·
5,009 Posts
Seachem Phosphorus is an alternative, not an addition am I correct?
Seachem Phosphorus is actually made from KH2PO4 just like the dry fert. Plants need this fert too.
would it be OK to add Iron on top of these two things? if needed?
Sure, just don't add iron to any product that has phosphorus/phosphate in it.
 

·
Registered
Joined
·
52 Posts
you add in macros one day then micros the next (plantex, iron ) and I would do as someone else mentioned buy you some HC from a hobbiest who has it growing already in thier tank , much better luck there keeping it alive , IMHO but I also dose excel every other day , but I use diy co2, so that may be why it works well for me . GL ~~
 

·
Registered
Joined
·
24 Posts
Discussion Starter · #15 ·
you add in macros one day then micros the next (plantex, iron ) and I would do as someone else mentioned buy you some HC from a hobbiest who has it growing already in thier tank , much better luck there keeping it alive , IMHO but I also dose excel every other day , but I use diy co2, so that may be why it works well for me . GL ~~
thanks that's a great idea. i think i'm going to try buying from an aquarist instead.

thanks everyone!
 

·
Super Moderator
Joined
·
12,014 Posts
you are right i didn't know about the EI method before making the purchase. i think they follow the typical formula below so i'm going to try to adding KH2PO4 separately as suggested by Left C and see how it'll work out.
As mentioned several times already, the PMDD dosing method based on the Sears and Collins article from years ago is very outdated. Keeping phosphates as the limiting nutrient is not a good way to prevent algae; in fact, it is a good way to promote algae. I believe Tom Barr has mentioned that he has kept tanks with 3 ppm (or perhaps even more!) phosphate with no ill effect. As long as your nutrients are in balance, then your plants will be happy.

3/4 tsp of K2SO4 and 3/4 tsp of Trace a week would translate to 9ml of PMDP a day if my math is correct.:eek:
This is correct. PMDD uses 1 tablespoon of chelated iron mix (CSM+B) dissolved into 500 mL. This is the equivalent of 3 teaspoons dissolved into 500 mL. Adding 9 mL at once would be 9mL/500mL * 3 teaspoons = 0.054 teaspoons. If you added 9mL everyday, you would be adding 0.378 teaspoons per week. This is equivalent to EI's dosing of 1/4 teaspoon, 3 times a week.

However, keep in mind that in EI dosing, you must carry out a 50% water change once a week, so in reality, you will probably need to add a bit more of the PMDD mixture to obtain the same amount of trace mix that is required.

More importantly, however, is the fact that PMDD does not contain the necessary other nutrients. For example, PMDD is severely lacking in KNO3. You will notice that, using the same calculation from above, adding 9 mL of PMDD once a day, everyday, will be the equivalent of 3/4 a teaspoon of KNO3. However, EI dosing calls for 3/4 teaspoons of KNO3 to be added to your tank 3 times a week!
 

·
Registered
Joined
·
2,328 Posts
Aquariumplants.com sells a powder mix they call PMDD that contains the following: "A blend of hydrated magnesium sulfate, potassium nitrate, potassium sulfate, and Miller Microplex trace element mix. Powdered mix can be used as a pellet component or can be added to water to make liquid fertilizers. "

I believe they call it PMDD because they buy it from www.plantguild.com who is an old timer hobbyist who started selling it back when people knew what PMDD was. Fertilizer is all the same basically, no matter what name it has. Its what you do with it that matters. Anthony, just because its called PMDD doesn't mean its being used according to the PMDD method. I think AP is just using the name without following a formula based on Sears and Conlin. I don't know if this stock solution is true to the Sears and Conlin formula or not, but EI is not the only "method" being used today.

For five years I have been growing HC that was emersed without any problem at all. There really is no difference between emersed and submersed HC. Thats an urban myth. The Barr method is growing it emersed in the aquarium, not submersed. If emersed grown HC melted when you added water, then tom barrs method of growing it dry in a closed aquarium would melt as soon as you added the water, and thats obviously not the case.

I don't think you have figured out the cause your HC problem here yet, but i hope you will check back in 3 or 4 weeks at least and tell us how it has gone.
 

·
Registered
Joined
·
24 Posts
Discussion Starter · #18 ·
approximately 70% of the 4th pot has melted and some are still melting. but most of the clumps appear to be growing, forming runners that have firmly attached to the substrate.

the problem is that they grow very slowly and the leaves are tiny, about 1/3 the size of the original leaves (which have all melted). could this be the lack of macro nutrient or light? i have been dosing 9ml of PMDD daily and nitrate level has been over 20ppm so i think the only things left to look at is phosphate (which is coming in the mail with Iron and Nitrate) and light. these bulbs are new so i think 3WPG might not be enough. should i add more light? i have another 130W 50/50 strip from USA Current.
 
1 - 18 of 18 Posts
Top