[peridot]

Hello everybody!
Question: Is Seachem's Equilibrium appropriate for an El Natural tank?

I am an enthusiastic and fairly experienced El Natural fan. We have been thru a move and our source of water has changed. I am now in the odd position of having to run an El Natural tank when my only source of water is RO water (Our well is contaminated with sea water, so all of our household water is RO) Have been using Seachem's Equilibrium as recommended rate; the product is advertised as being designed to "establish the ideal mineral content for the planted aquarium" The tank has become loaded with short very dark green fine textured fur; the plants are growing only slowly, even the duckweed is kinda slow.

The details of the label are as follows
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Soluble Potassium (K20) 23.0%
Calcium (Ca) 8.06%
Magnesium (Mg) 2.41%
Soluble Iron (Fe) 0.11%
Soluble Manganese (Mn) 0.06%
Derived from: potassium sulfate, calcium sulfate, magnesium sulfate, ferric sulfate, manganese sulfate.

Elemental potassium is present at a concentration of 195,000 ppm (19.5%). Archaic fertilizer laws force us to list potassium in terms of equivalence to a material that is not present (K2O) rather than the more scientificaly sound method of simple elemental equivalence.
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Is Equilibrium appropriate for an El Natural tank? I have a lab background and a scale; if I had a recipe I would consider making up my own personal brew if that is likely to be beneficial.

Many thanks for your patience with this arcane question.

Mary

 

[Jark]

I would check your tank perimeters. What is your tank size, lighting,,,... If it is the same setup you had at your old place is it getting more/less natural light this time? Near a window,..in a basement? Also check your nitrate levels. If they have bottomed out you will have little plant growth and get blue green algae growing. How long has the tank been up and running?

Can you post a picture of your tank and/or the green fur? depending what that is it could point out your problem.

How fancy of a RO unit are you running and recently maintained? I don't know much about them myself but I know they can vary a lot depending on the unit. The one here in lab will get taken down often when levels get off or other problems. Any way of measuring if salt is getting though?

As far as Equilibrium is concerned I have found it to be a good product so far. You could check your levels though. You might also want to look into dosing micro nutrients sense clean RO water is giving you nothing. Something like this http://www.aquariumfertilizer.com/i...rnEdit=2&Returnitemname=&ReturnShowItemStart=

I use seachem equilibrium in my 55g and 5.5g tank. In my 55g I use tap water and I have very alkaline soft tap water. KH very high but the GH is very low. If I don't use equilibrium or some other GH booster I get potassium and calcium deficiencies. I have my 5.5g at my bench in a lab and I use the lab RO water with equilibrium in it. Instead of the recommended dose I use this calculator http://www.aquaticplantcentral.com/forumapc/fertilator.php I think they come out fairly close though. I add a little micro nutrient mix every once in a wile.

Also if you are doing no or few water changes, as is common in El Natural tanks, your plants might be using up what nutrients are supplied in the equilibrium. I would test your water KH and GK. The GH can drop dramatically over time as your plants soak up the K Mg and Ca. If it is low adjust it back up with the Equilibrium.

Tom Barr also uses equilibrium in a dosing strategy in "Barr style" low tech tanks. Doing this might be useful. http://www.barrreport.com/showthread.php/433-Non-CO2-methods I use equilibrium similarly if I notice deficiencies.

Check your plants for deficiencies. Any holes, yellowing, curling, change in leaf size or shape? Here is a diagram of some common deficiencies. Different plants present different symptoms but this is a good start. http://emergingintuitions.com/aquac...uploads/2010/11/plant-deficiency-labeled2.jpg

 

[vicky]

Yes and no. There is nothing wrong or un-el-natural about adding nutrients when needed. The problem with SE is the sulfates. I don't have time right now to look up the reference, but it reacts to cause hydrogen sulfide gas, toxic to critters and perhaps plants as well. Use it in a pinch, but look for forms of the same minerals other than sulfate.

 

[Jark]

I haven't heard of people having problems with sulfates in SE. Let us know if you find the link. Before I started using SE I used some potassium and calcium chloride I had in lab to adjust the levels up. I used to also half the RO water with tap.

Do you remember if the sulfates were an issue with normal doses with water changes, or if is more an issue with constant dosing without water changes? I you keep adding it without doing water changes it could build up if you just keep adding it or using it in water top offs without water changes to reset everything. Tom Barr's GH booster is all sulfates too. Tom's Dosing methods do involve large regular water changes though.

 

[vicky]

http://www.aquaticplantcentral.com/...rum-calcium-dosing-increase-5.html#post467158

The link should take you to Diana Walstad's view of sulfates, right here in this forum, just a few years back. If you have the time, read the entire thread, but it is lengthy.

 

[Jark]

That's interesting. I hadn't run across that before. I guess the consensus is, it is a problem specific organic substrates like ours. There wouldn't be a problem in most other more dosing dependent tanks because they generally don't use soils or other heavy organic substrate.

Also it is only a problem in anaerobic substrates. The substrate depth and root density would be big factors in weather the sulfates are a problem. I haven't seen too much of a problem yet. I have a lot of very root heavy plants that are keeping it well aerated though.

I have heard of people getting toxic hydrogen sulfide pockets in non-Walstad tanks as well though. They weren't necessarily relating it to dosing, but instead to poorly aerated/rooted substrates with high mulm buildup. I don't know if they were using sulfates though.

The thread mentioned substituting CaCl2 in place of CaSO4 but I didn't see any alternatives for the K2SO4 for getting K. I guess I could use KNO3 but then I am jacking up my Nitrates which I don't really need. I guess subbing in CaCl2 would be a start. MgSO4 isn't as much of a concern because of the low dose.

I mainly use the SE for the K and Ca second. I'll have to test my water more and see how much KNO3 I can get away with. If you run across a good alternative to K2SO4 that is readily available let me know.

 

[vicky]

I use potassium carbonate, K2CO3. My local home brew supply had an ounce for $1.25, and it seems to be working fine. I have not pursued getting larger quantities yet. Did you see this post earlier in the thread? http://www.aquaticplantcentral.com/...rum-calcium-dosing-increase-3.html#post133258

It seems a mixture of anions might be preferred. Too bad Equilibrium is *all* sulfates. Still, many use it successfully. Since OP asked if it was appropriate, I felt I should at least bring this up.

 

[peridot]

Thank you for wonderful replies. Definately sounds like Equilibrium is not a good way to go especially when trying to get GH up around 6 or 7 grains. I will therefore work up home brew using info in Ms Walstad's book and in the discussion you linked to. Its either that or go, bucket in hand, begging at my neighbors up the road.

Mary

 

[Jark]

Hmm. I found KCL sold as table salt substitute for cheap. Might check at a local health food shop or online. http://www.imedmart.com/NOW/Potassium-Chloride-Powder-Vegetarian/8-oz.html?cmx=8X0D21&refx=FR00GX

 

[Cincy_bob]

I use K2CO3 as part of my remineralizing salts for the RO change water in my high tech EI tank. Potassium carbonate lets you get a good concentration of potassium ions into your water without resorting to K2SO4.

However, one thing to be aware of is the high pH of a K2CO3 solution. The pH of my change water measures over 9 after I add potassium carbonate to the RO water, and I should add that I am running a VERY low level of carbonate buffer in my tank (1.2dKH, 4.5g K2CO3 in 150L RO water).

I typically aerate the water in my reservoir for 24 hours after adding the potassium carbonate (and before adding the calcium and magnesium salts) in order to drive the pH back down into the mid-7s. I'm not a chemist, but this is what I think is going on:

K2CO3 + H2O --> 2(K+) + HCO3- + OH-

OH- + CO2 --> HCO3-

As atmospheric CO2 is dissolved in solution, the CO2 fixes the hydroxide ions forming bicarbonate ions. (Chemists, please chime in if I have something wrong here.)

Without aeration, I find that I get calcium deposits on the walls and bottom of my change water reservoir and on my submersible heater. At a high pH, I believe the Ca++ ions readily combine with CO3 to form CaCO3, which falls out of solution at a high pH. However, I find the problem with calcium precipitation is resolved by aerating the buffered RO water to drive down the pH of the solution prior to adding the calcium and magnesium salts.

As for the potential for excess sulfates, I have not personally experienced any problems, and I have been using CaSO4 and MgSO4 for about a year now to obtain nearly all of the calcium and magnesium in my remineralized RO water. However, I have also been routinely performing 50% weekly water changes.

I would be concerned about elevated TDS and sulfates if large quantities of CaSO4 or MgSO4 were being used to replenish calcium and magnesium without the benefit of regular water changes to keep the residual SO4 in check. Taking some periodic measurements with a conductivity meter would allow you to keep an eye on the situation.

 

[vicky]

Well, that's interesting, but most of us do el natural to get away from 50% weekly water changes.