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Water Change Aeration

2934 Views 8 Replies 5 Participants Last post by  jellopuddinpop
Hello everybody.

I'm relatively new to being serious about the hobby of fishkeeping. I searched this forum, and the wise God google with only some topics brushing on my question. So I turn to you glorious gurus!

My question is, when I am doing 20-30% water changes in my 20 gallon H tank, with a PH of around 6.8, should I aerate the water while it sits before I add it to my tank?

I saw a lot of information for aeration regarding salt water, but not about freshwater. I currently have a heavily planted tank with no CO2 yet (I'm still waiting on my diffuser to arrive). I read that too much movement of the water may "push" the CO2 out of the water. But when I do a water change, I immediately fill the bucket, treat it with prime and then let it sit for about 3 days (right now as the tank is still relatively new) before I do my next water change.

I have a small heater that I put in the bucket to keep the water around the same temperature as my tank, but it has no movement while it sits. I do cover the bucket (with my "dirty water bucket") because any open water source in my house is free game for drinking water and pet hair.

There are currently 5 harlequin rasboras and a snail in the tank. Eventually it will house 5 panda cories, my betta, 10 rasboras a mystery snail or two and a small colony of shrimp.

So moving forward with the maturing of the tank, should I begin aerating the water change water? Or is what I'm doing ok to let it sit covered, treated with prime and a small heater.
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It's not water movement that causes CO2 to dissipate from water, it's when the water surface is broken, like by waves or aeration.

I'm curious, why do you leave your water sit for 3 days?
Yeah, Prime works instantly to de-chlorinate water so there's no need to have it set for any length of time. Many add Prime to the tank and fill straight from the faucet.
It has long been held that any aeration will negatively reduce CO2 in the tank. This is really not the case as Tom Barr has recently pointed out - oh, there's a very slight reduction perhaps, but not significant enough to be concerned about.
It's not water movement that causes CO2 to dissipate from water, it's when the water surface is broken, like by waves or aeration.

I'm curious, why do you leave your water sit for 3 days?
Mostly because I have a small heater, so I want to give it time to warm the water since it would be purely through radiation since there is no current to speak of. Only what is created by the heat. So like, really slow convection.

My concern about adding warm, or at the very least tepid, water from my hot water tank would be any residuals from the tank itself. Like how you aren't supposed to use hot water from the tap to cook your food because of the bacteria that forms from sitting.

I live at the base of a mountain near the source of our municipal water, so water straight from my tap comes in quite cold. Like, fridge cold.

My water tank is only 2 months old though, if that. But you think I would be ok just turning up the temperature a touch, and adding it straight to the tank?

I have just let it sit because I'm already doing a water change, so what's one more bucket of water really.
Water out of the tap can be low on oxygen. Since your letting the water stand for a few days, you likely don't need to do more in the way of aeration. If you want to so something anyway a small powerhead, with the flow directed to it just breaks the surface will do nicely.
When you think about it, the water going into your hot water tank has been treated to kill germs and at 120F, germs won't grow! .... besides the bacteria in your fish tank far and away exceed any found in your hot water tank - so the hot water can be used safely. With Prime in the tank, and the right adjustment of hot and cold water, you could fill with a hose from the sink and no more hauling buckets! Oh, and once you get a good mix, take a sharpie and mark the back side of the faucets - that way you'll index them (close enough) for every time you use them!
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Ah, ok awesome!

I will probably still haul buckets because we have one of those fancy faucets that pulls out with an interchangeable spray nozzle and normal flow. I don't think my landlords would take too kindly to me taking it apart so I can fill my aquarium.

But I'm glad that I can warm up the water! I have an external thermometer my husband uses when he brews beer, so I can get an accurate reading on temperature as it's being filled. I will just put the little heater back into my quarantine tank.

That means that I can put the buckets away and just look at my tank without all the clutter!
99% of all faucets have a simple aerator on the end that screws on. It is simply unscrewed and a hose adapter attached. But if you have a small aquarium and don't mind hauling buckets...:smile2:
Oh, and once you get a good mix, take a sharpie and mark the back side of the faucets - that way you'll index them (close enough) for every time you use them!
This is friggin brilliant.
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