Bleach Dosing?

cacas

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Hi everyone. Recently I met up with a pretty 'unique' reefer in my area. I won't say I agree with all his methods, but his tank does look stunning. Unfortunately I forgot to take pictures 😭 .

Anyways, one thing that he did is doses chlorine bleach!?!?!!?! I was taken aback. I honestly thought that he was joking with me but he actually did.

Apparently he dosed a "drop" (however much that is 🙄) of bleach per 15 gallons. He seemed quite convinced that this was a key factor in his success.

I am strongly skeptical that this is having a beneficial effect in his tank, and definitely do NOT agree with that practice. Anyone have thoughts/input on this? Is this actually a real technique/method? I would be surprised if it is.
 
I'm intrigued, a little.

I don't care for this dosing of hydrogen peroxide in a display tank (in a QT tank, maybe). Hydrogen peroxide is an indiscriminate oxidiser that works on anything organic, good or bad.

Now, you're talking about sodium hydroxide (bleach) which is a far more powerful oxidiser. I can't see how dosing this is beneficial, but, for the sake of argument, perhaps this is running the fine line between beneficial and detrimental 🤪

I will say that in the world of undergraduate bio and chem labs, it's often suggested that one 'drop' from an eye dropper of an aqueous (water based) solution is approximately 1 mL. Therefore, you could say that the dose is 1 mL/15 gallons of water. To me, that doesn't sound like enough to do anything, good or bad, but the hydrogen peroxide people swear by their very low doses, so I don't know.

@Randy Holmes-Farley do you have a minute to offer some insight here please?
 
Yeah honestly I am still quite shocked. Who would have thought? Still not a believer.
 
No Way Randy GIF by Zack Kantor
 
What was his specific reason for dosing bleach? I get that something is being dosed, but the why is what want answers to. This is not like dosing ammonium chloride, or ammonium bicarbonate for low nutrient systems.

hypochlorite also found in sodium hypochlorite, or rather it makes up part of the sodium hypochlorite, but it reacts with bromide in salt solutions to form bromate, which itself is high oxidizing compound. It’s actually formulated by the mixing of bromide and ozone in municipal drinking water. I would say possibly toxic in marine water, or at least dangerous if dose is off my just a smudge. I would venture to say possibly higher Orp numbers being the reason? Saying cleaner tank water?

If you get to ask the person post the reason if given one. And if you don’t meet him again, I guess we’ll never know for sure.
 
Randy would be the expert on this, but I was curious and got an AI to give a scientific analysis. The conclusion was: From a chemical and biological standpoint, dosing bleach directly into a display aquarium is an unbuffered, high-risk attempt to replicate the oxidative benefits of ozone or hydrogen peroxide.
While a tiny dose (1 drop per 15 gallons) may occasionally be consumed entirely by organic demand without causing visible catastrophic damage, it offers no advantages over safer, controllable alternatives.

So sounds like this guy is riding the razors edge with this. If he ever does it when his nutrients are bottoming out he is going to do some serious damage it sounds like.
 
Randy would be the expert on this, but I was curious and got an AI to give a scientific analysis. The conclusion was: From a chemical and biological standpoint, dosing bleach directly into a display aquarium is an unbuffered, high-risk attempt to replicate the oxidative benefits of ozone or hydrogen peroxide.
While a tiny dose (1 drop per 15 gallons) may occasionally be consumed entirely by organic demand without causing visible catastrophic damage, it offers no advantages over safer, controllable alternatives.

So sounds like this guy is riding the razors edge with this. If he ever does it when his nutrients are bottoming out he is going to do some serious damage it sounds like.


Exactly why I said what I said above haha. I guess AI is smart once in a while or on point 😆

It’s being used for higher Orp numbers, or to have cleaner water. Not risking reef tank issues, for minimal gains that can be achieved in other safer ways!
 
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I'm intrigued, a little.

I don't care for this dosing of hydrogen peroxide in a display tank (in a QT tank, maybe). Hydrogen peroxide is an indiscriminate oxidiser that works on anything organic, good or bad.

Now, you're talking about sodium hydroxide (bleach) which is a far more powerful oxidiser. I can't see how dosing this is beneficial, but, for the sake of argument, perhaps this is running the fine line between beneficial and detrimental 🤪

I will say that in the world of undergraduate bio and chem labs, it's often suggested that one 'drop' from an eye dropper of an aqueous (water based) solution is approximately 1 mL. Therefore, you could say that the dose is 1 mL/15 gallons of water. To me, that doesn't sound like enough to do anything, good or bad, but the hydrogen peroxide people swear by their very low doses, so I don't know.

@Randy Holmes-Farley do you have a minute to offer some insight here please?
Just to note: Bleach is sodium hypochlorite not sodium hydroxide. Sodium hydroxide is used by some people to boost pH and alkalinity.
 
Bleach dosing is often done to increase ORP/Redox which in itself is a measure that is really complicated and hard to interpret correctly. Many people believe that a low ORP means it's a "dirty tank", but if you test freshly mixed saltwater it will often give you a very low ORP and water changes will (at least in the beginning) drop ORP, showing that it's not that easy.

Bleach dosing (in adequate proportions) in itself won't cause your corals or fish trouble as long as you make sure it reacts before significant amounts are taken up by your tank inhabitants. There always is some free chlorine in a reef tank so it's not completely foreign to their bodies, but certainly not in concentrated form.

The benefit is still questionable as chlorine will react to byproducts such as chloramines which aren't really something you want in your tank either. That's also why I sterilize my Phytoplankton culture media with a pressure cooker/autoclave instead of bleach besides some other benefits this offers.

In the end it's the dose that makes the poison. There are certainly better ways to increase ORP/Redox If that is actually something you want to achieve. Bleach dosing as well as ozone and other oxodizers like hydrogen peroxide have been successfully used against some dinoflagellate outbreaks but this remains a very experimental approach and should only be tried if nothing else works.
 
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Long ago a club member’s then wife admitted in a separation argument to to regularly dumping bleach into his 150 display becuse she hated him and his fish tank.
...some people are just monsters. Making animals suffer due to differences with their partner. It's just beyond me why people act like that.
 

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