The 50% Water Change

[BenB]

This has been beat to death for years. So why not continue.

As I've wrestled with algae, I've been doing around 70% - 80%+ water changes. I was thinking tonight though that maybe very large water changes too often could be more disruptive to your tank and have a negative impact. I'm not saying, never do a large water change. I'm saying very large water changes on a regular basis as opposed to the exception. What do you think?

 

[Unexpected]

I disagree, multiple huge water changes wipes out algae from my experience, but only if I dose my storage water ahead of time (front load macros). That said, doing all that work is just too much work and others can solve these problems with just weekly 50's. There's something I'm doing wrong with my 2 aqua soils tanks. So I've said f it, and have gone back to just doing the 50%. I'm completely baffled and now I've convinced myself this Netlea soil has poisoned my tank. But it's important to me to figure out what the hell I'm doing wrong and be able to fix it with just the weekly 50 changes.

 

[Mr.Shenanagins]

I vacuum and drain/refill at the same time. This results in around 70-80% WC each time, I’d argue it’s better for the tank. I think if your tank is matured and you have good plant mass, you’re mainly ridding the tank of the excess organics and not the BB that keeps things running smoothly. I could be full of S**t too I’m no biologist, just purely observation.

 

[Pepere]

I was thinking tonight though that maybe very large water changes too often could be more disruptive to your tank and have a negative impact.

Well if that were true, rivers would be in a world of hurt…

But, on the other hand, stability is important. If water changes result in fluctuating calcium and magnesium levels, as well as macro levels, plants might be exerting energy to reprogram themselves for changing levels…

My personal experience with water changes have been nothing but positive…

 

[BenB]

Well if that were true, rivers would be in a world of hurt…

Well, I'd argue that for a river system, constant water change represents stability. Not really an apples to apples comparison to our tanks.

But, on the other hand, stability is important. If water changes result in fluctuating calcium and magnesium levels, as well as macro levels, plants might be exerting energy to reprogram themselves for changing levels…

My personal experience with water changes have been nothing but positive…

Yeah, that's kind of what I'm pondering and @Mr.Shenanagins hits on it as well. Which is the goal? Stability to control algae or disruption?
If I were to guess, I'd say it might be tank/situation specific.

 

[Pepere]

Well, I'd argue that for a river system, constant water change represents stability. Not really an apples to apples comparison to our tanks.

Well that was my point. Water changes in and of themselves are probably not a problem, while fluctuating nutrient and mineral levels probably are.

 

[Art]

Great topic!

I once posted on Facebook that water changes could be minimized or eliminated using carbon. I'm still stinging from the flame war that erupted!

I asked, "What do water changes do that people feel keeps algae away?"

No one could give me a straight answer because the truth is no one knows exactly.

A fact is that a water change does cause fluctuations in many things that we feel should be stable. Is this good or bad?

We also know that a 50% water change should only remove 50% of what you feel is bad. In other words, it reduces the amount of something but doesn't eliminate it. Is this good or bad?

If the point is to remove DOC because it causes algae, then running carbon would be a better solution because it will remove 100% of it versus only 50% of it as the water change does. Would you agree?

Having said all of the above (and I'm interested to hear your thoughts), I am still a member of the weekly water change club because I have seen that my tank runs better with it than without it.

 

[Pepere]

I'm still stinging from the flame war that erupted!

That is a pity…. I am all for experimentation and challenging norms and then sharing results..

If the point is to remove DOC because it causes algae, then running carbon would be a better solution because it will remove 100% of it versus only 50% of it as the water change does. Would you agree?

I don’t know Art, water changes are just too cheap, quick, and efficient….

The world may never know…

 

[Art]

I agree. That's why I am proud to wear the club t-shirt.

 

[Art]

Hopefully, they have changed from this:

 

[BenB]

I once posted on Facebook that water changes could be minimized or eliminated using carbon. I'm still stinging from the flame war that erupted!

No surprise there. I honestly believe that different tanks and different situations might require different strategies, but FB is never going to go for such versatility in thinking. Forums are going to be a bit better.

 

[Kwyet]

The purpose of water changes isn’t just to reduce algae though. Water absorbs all kinds of contaminants from the air, and also builds up hormones from the stock. Water changes keep those things under better control.

 

[BenB]

I could be full of S**t too I’m no biologist, just purely observation.

I didn't know this forum would let me cuss. This makes me damn happy!

 

[ElleDee]

I think this depends some on your source water. My city water is great - very soft, low tds no nitrogen species, and has seemed pretty stable over the years. It's not quite RO water, but close enough. I can do large, frequent water changes without a second thought. But if I had terrible or variable water the gains might be much smaller. Also, my parents' well water has a crazy amount of co2 in it and it might not be safe to do large water changes with livestock.

As it is, the size of my water change is tied to the containers I'm using more than any percentage of the water. For my 20- and 22-gallon tanks, I do 8 gallon water changes because I have two 5-gallon buckets that I put 4 gallons of water in so I can easily carry them without sloshing. For my big tank I have a plastic tote that holds 15 gallons that I fill twice. If it were 17 or 13 gallons I probably would still fill it twice and adjust my fertilizer/minerals accordingly, you know? I just found the biggest container that would fit in my sink and went from there.

 

[Koan]

just found the biggest container that would fit in my sink and went from there.

But you miss out on all the Python fun!

.. backspray all up the kitchen sink windows when you haven't tightened it down enough..

.. smacking things off your counter onto the floor..

.. dog / children getting tangled in it..

.. sprinting across the house to shut it off because you were running it too fast and almost flooded the tank..

.. forgetting to close the end and dribbling a great big puddle on your carpet..

 

[BenB]

But you miss out on all the Python fun!

.. dog / children getting tangled in it..
.. sprinting across the house to shut it off because you were running it too fast and almost flooded the tank..

I'm not the most nimble anymore. I can relate to this and I've had to change my process.
Me sprinting across the house and getting tangled in the hose is a valid concern these days.

 

[Mr.Shenanagins]

@Koan I have a valve at the end where it empties into the tank for that reason. The sink is free flowing and I have a switch at the end where I’m filling the tank to turn it off. That J hook is a great piece of engineering from Python but they failed on the threads. I have had to mess with it a few times because it likes to drip if it comes loose at all. I need to add a swivel there so it doesn’t unscrew itself from all the moving around.

Side horror story: years ago when I was younger I flooded my whole basement floor because I was filling my turtle tank at the time and walked away. This resulted in about 1-2” of water on one side of the basement. It was my parents house at the time and needless to say, it was a learning experience. I tore up the carpet, laid it all out on the driveway on a nice sunny day and power washed it with the help of oxiclean. I installed new padding, and once the carpet dried out I reinstalled it. An unnecessary proud moment for me and a lesson for everyone else DONT WALK AWAY

 

[Art]

DONT WALK AWAY

I can't count how many times a flood has happened to me because I walked away. The curious thing is that I know this is a HIGH probability if I walk away but I still seem to talk myself into ... walking away.

 

[Pepere]

Python needs to make a hang on the tank float valve to shut off the water when it gets to a set level.

But personally I would be happy if they made their fittings more watertight….

 

[Count Krunk]

Personally my goal is to have as few water changes as possible.

I havent had a high tech fw tank yet so I've yet to test this method there.

It works very well with bright light low ferts walstad tanks .