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ReverseOsmos wastewater

H..

Member
Joined
4 Oct 2011
Messages
257
Location
Alnö
I have really good tapwater here in mid Sweden, soft, and low in NO3, PO4, and so on. But I have this RO filter for my saltwater tank . And I was using the wastewater from the RO filter to make waterchanges in my planted tanks, but there was an issue with this method.

I got massive black bush algea BBA atacks when using RO wastewater, so much that it covered older leaf edges compleatly in a few days, and not only in one tank and ones. This was an clear sign in every tank when I was doing bigger waterchanges (50%) with the RO wasewater.

I tryed to save som water, but the problem was so massive I have to waste it in the drain now.

According to the municipal water supplyer, some parameters are:

https://msva.se/wp-content/uploads/2016/12/Dricksvattenkvalitet-Wifsta.pdf
Ph ---7,7
Ca ---15ppm
Mg ---1ppm
2,4 ---°dH
NO3 ---2,2ppm
PO4 --- noshow
SO4 ---5,3 ppm
When I make 25 liters of RO water, I also make some 75 liters of wastewater, what can I expect theoreticly of the water to be here?
And what is it with BBA that triggers it so badly

H.
 
Reverse Osmose works with a semi permeable membrane as filter, the water is pushed through under pressure. The microns in the membrane are so small it pushes pure water molecules through and the bigger particles/molecules are flushed out with the waste water. A good filter has a 95 - 99% effectiveness. And a waste of 3l to 1l RO is pretty common, some installations waste 5 to 1.

With 3 to 1 and a 99% pure output it's an easy formula if you have to complete report, to know what's in the waste.

Example for the Ca 15mg/l x 3 + 15mg = 60mg/3l = 20mg/l approximately it will be a tad less depending on the purety output 95 -99%.
For the rest you can use the same formula since all is in mg/l

Why it triggers BBA?.. Good question :) I wouldn't know a conclusive answer.. Reading the forum about BBA in theory the usual main suspects are High Bioload vs Biological Oxygen Demand vs sufficiently healthy growing plantmass (Preferably fast growing).

High bioload can be caused by bad husbandry (lots of rotting debri), lot of melting unhealthy plantmass, over stocking and or to much feeding.

BOD, the Bacteria that need to convert all this bioload use Oxygen, if it aint in equilibrium there will be a accumulation of waste products feeding the algae instead. (High temperature tanks have less oxygen than low temperatur tanks).

Sufficiently healthy (fast) growing plantmass also cleanup waste products and it possitively aids the BOD with providing oxygen. Not having this, feeds the algae instead of the plants.

Other side factors in play with the above 3 are light, CO², flow and fert regime.

It all needs to be in sync. Thus it is hard to say what is off in your case(s).

As said these are the most common usual suspects, but experiences differ and lots of theories are out there. We have 2 stickies dedicated to it and still we are wondering.. :)

https://www.ukaps.org/forum/threads/what-exactly-causes-bba.36674/

https://www.ukaps.org/forum/threads/what-exactly-causes-bba-part-2-bacterial-imbalance.38375/
 
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Thanks zozo for reply.

So an increase of wastewaters ppm´s by x 1,33. OK, thats easy to understand

If I make an 50-75% waterchange i will have lots of microbubbles, just as an normal waterchange, but much more, so it looks really oxygenized after, this i suspect is one of the triggers, and perhaps something else has increased due to ppm increasement.

About bioload, there is not much cause i grow mosses and keep an small amount of shrimps, and they do ok with very litle feeding(barly anything)

H.
 
The main cause is introduction, but that aint hard, algae spores fly all over the planet and or are already latntly present on newly introduced plants.
Than you need to cut out the main factor that is favoring and feeding algae and since it is a game of sevral factors. It could be anything that is very hard to determine without much more additional information.

Examples are it could be light if it is to intense for the types of plants you grow. Some plants keep growing relatively slow, than high light intensity and excess fert supply can favor algae growth. Or high intensity and to little fert supply also. Bioload can be back calculated to food supply, it raises ammonia levels, plants can take up ammonia directly as food source. If the plant doesn't the algae wil after all they are very plant like and favor simmular conditions but need less of all to party..

Bioload can be encreased by unhealty growing plants with melting leaves, it realeses sugars and protein etc. into the water column and into the substrate if leaves melt roots can do too. It's again a possible alge food source. Plants can melt in an excess of light others in lak of light it all depends on plant species.

Flow distribution can cause plants in dead spot to be rather unhealty.

You don't mention if you use CO² than there is more to say about flow and light and ferts etc. I asume you don't and do go into it.

Thus there are multiple factors in play, it could be one but most likely a combination.. :) If the conditions are favoring BBA it also can grow in the darkest spots of the aqaurium. It all depends.

But if you can give a detailed specification of the tank in question.

Lights (intensity - duration)
Volume
Turnover
CO² no CO²
Fert regime
Stocking
Plants ( how many + species)
Maintenance regime
Pictures :thumbup: say more than 1000 words

and i propably forgot a few. :)

Than somebody experienced maybe can tell you points of interest to look at or ask more questions..
 
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If you feel bad wasting water you could always use it to flush your toilet.

There's not much else it's good for.
 
Hi all,
When I make 25 liters of RO water, I also make some 75 liters of wastewater,
You should get less waste than that because your starting water is pretty close to RO anyway. If your water supply is low pressure, or very cold? it will effect the ratio of RO to waste.

Your waste water is still much better quality than most of the tap water in the UK, so I don't think it is responsible for your BBA issues.

On your water report it has a conductivity value of 10 milliS m-1, which is equivalent to 100 microS cm-1. If you have a conductivity meter then your waste water should be somewhere near 135 microS cm-1.

cheers Darrel
 
Well thanks all for help.

I have multiple tanks with different setups, som with CO2 som without, a few smaller and some bigger.

I find them all quite good kept, with just a few fish, but mostly shrimps, so the bioload is rather low generally. i use PMDD in some of them, and the tanks stay fresh with good growth and moderat but not low lighting. One of them is highlightes and some plants here are more sensitive, Bolbitis heteroclita "difformis" is very greatful for BBA to attach.

The tanks are all fresh untill i do bigger waterhanges with wastewater from the RO. This is so significant and directly connected to RO wastewater and I have experimented for the last six-nine months. Ido think dw1305 there is an issue with using wastewater definetly. I probably use 20-26 dedree water mostly.

One significant different i notice is that there are more microbubbles after an waterchange, on tank glass and from bubbling plants. What is this? Oxygen from photosynthesis or what?

Cheers at friday!

H
 
sorry no conductivety meter

H
 
and some plants here are more sensitive, Bolbitis heteroclita "difformis" is very greatful for BBA to attach.

Yup the <epiphytes> growing submersed are all rather slow growers and susceptible to algae attack. I've also experience the B. heteroclita the most difficult fern in it's genus. Tried it a few times in high tech setups and everytime it got eaten away by bba. :) In this case i suffered Staghorn (BBA)

In nature these plants rarely grow submersed, mainly they grow near wet places in the splash zone, attached to rock or wood. In botanical terms they are the i.a. facultative lithophytes. Meaning growing on rock and beyond, on wood or sometimes even on forest soil. But main characteristic of these types of plants, they have evolved to grow in poorly fertilized conditions,, mainly feeding on what the bacteria living at their roots provide, have a very slow uptake and mainly only survive in shaded and cooler spots. The ones that survive sunny spots grow in the splash zone on rock etc sticking out of the water.

It can be very challanging to grow these plants out of their comfort zone, permanently submersed, healthy and algae free. The placement of these plants in the scape should be well thought out, especialy if kept together with plants requiring a higher light intensity and higher fert regime. Than if the balance is off and bba starts to party, these slow growers are the first to suffer. The ones that are placed in a location that doesn't respect it's natural requirments even sooner.

Thus that rather mysterious balance to keep algae out is not only in the parameters, it also is in knowing your plants and its best spot in the given conditions.

When it comes to BBA or algae growth in general, i can understand that you are dead set on it, that adding your waste water parameters must be the root cause. You are not alone in this, there are numerous threads and numerous different experiences with changing one specific parameter causing a BBA outbreak. E.g. many experienced BBA outbreak after dosing extra Fe to the tank, than open a thread and report dead set that the extra iron is the root cause. Than if you read on than you only can come to the conclusion that this isn't true for everybody. Many use Estimative Index as fert regime, that goes by the principle add more ferts than you need to prevent ever running into a shortage and reset the water column with a weekly water change. And they do not suffer from BBA, than if you compare both situations in PPM the one with using IE as fert regime has a permanently higher iron content than the one claiming dead set extra iron is the cause.

There are reports of people switching liquid fert regime from Tropcia Premium to Tropica Specialized and suffer a bba outbreak (matter a fact i did too) and than report dead set the extra Nitrogen in the Specialized version causing it (that i didn't). Tropica even gives a warning for it on the botlles description. The question remains, what is different or better for the people using it and not suffering from bba?.

It goes on and on, than it's this than it's that about everything that can change has been named as root cause.

And that is how we ended up with a 2 part sticky "What causes BBA" and still without a conclusive answer. :)

I also doubt that adding your waste water is the root cause.. Same as @dw1305 says, your waste water has better parameters as the average UK tap water. Same goes for me, if i compare your WC report with mine, your RO waste water contains less of everything than my tap water.

At the moment i keep 4 aqauriums, 2 are growing BBA the other 2 absolutely don't. The 2 that never grew it both are cold water aquariums. I did throw BBA infested plants in these tanks and it dies. The 2 that grow bba are heated tropical aqauriums. From this experience i could be dead set on stating temperature is the root cause. I believe it most likely isn't, but it definitively plays a role in its cycle.

That makes it complicated and rather frustrating steering you dead set on 1 cause, that isn't the root cause alone.. In 90% of the cases it's a combination of factors that need to change and 99% of us have BBA spores in our aqauriums.

You might want to read this journal from @Tim Harrison and his latest BBA battle he unfortunately lost. The plot thickens :arghh: is it a bad batch of DW that's the root cause? Unballanced bioload triggered by the wood? And if you want to see well kept aqauscapes, than Tim's journals are the ones to read. :)
https://www.ukaps.org/forum/threads/naturescape-venus-flytrap-flowering.52807/page-10#post-543234
 
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Hi all,
sorry no conductivety meter
It is worth getting one, even a relatively <"cheap low range meter"> will give you an accurate reading. It will also give you a quick check that your RO unit is functioning properly. Conductivity meters are the only meter that doesn't need calibrating before every use, they really are "plug and play".

You can use a hydrometer, (or more accurately a refractometer), for salt water, because it is much denser than fresh water, but the conductivity scale is linear all the way from DI water at ~0 microS cm-1 up to sea water at 53,000 microS cm-1 (5.3 milliS cm-1).

cheers Darrel
 
Thanks zozo, for explaining algea and slowgrowers.

And as you say, I am dead set on that my wastewater is containing parameters that triggers BBA.
I have earlier noticed that making less or smaller waterchanges is better for BBA, i mean it reduces BBA in my tanks. And therefor iwill make an experiment with my wastewater.

I will try to find an reservoar tank for my wastewater, so it can save water and let it set for some day, and later make an bigger waterchange with it. This will give me the same parameters, but letting the water be "mature". Beside i will run an tank and use "raw" wastewater for reference.

Cause i sense there is something with tha water that is triggering algea, these microbubbels i get after waterchanges trubbels me.

I once had an coductivity meter, but i did not know what the reading were good for, and eventully it dropped in to an tank, and was broke, didnt really miss it after,

Thanks all, Cheers

H
 
Hi all,
these microbubbels i get after waterchanges trubbels me
It is probably just the dissolved gases coming out of solution as the water warms up. Gas solubility <"declines with increasing temperature">. This is true for all gases.

You can see this happen when you boil an electric kettle, at boiling point the water can hold no dissolved gas and as the water warms up more and more gas comes out of solution.

cheers Darrel
 
Yeah Darrel. Thats is my new theory. I belive extra gases triggers my BBA outbreak.

BBA could benefit from extra oxygen or whatever gases there are in my tapwater.

Cheers
 
Hi all,
Thats is my new theory. I belive extra gases triggers my BBA outbreak.
that is probably as good a guess as any one else's.

I know they aren't to every-ones taste, but Red Ramshorn snails will control BBA. They don't eat the obvious BBA "tufts", but they graze the sporelings, so eventually you end up without BBA, or with it only on the bits of the tank that the snails can't reach. Have a look at <"BBA on sponge filters">.

In <"Is algae worse with LED lighting?"> it links to a scientific paper that suggests low light intensity and a long photo-period are the best conditions for Red Algae growth, so it may be that a shorter photo-period, with more light intensity, will discourage it.

cheers Darrel
 
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