Getting ready to doa water change...

[bishop_gideon]

But I just thought of an interesting question...

How do I know how much water I've taken out?

I've got a 75 gallon tank and I'm going to be using a Python draining thingy... how do I know when I've taken out XX gallons?

Is there some type of formula? 1/2 inch of water = 1 gallon or something?

Any advice?

 

[PoukieBear]

Most people change between 10% and 20% of thier water.

I calculate this in the stupidest way possible, but it works.

I eye-ball it. Just take out 1/8th of the water in your tank. If that's two buckets full, then remember that for next time.

 

[kraze3]

I use 5 gal buckets so if your doin a 10% water change of a 75 gal tank that = 7.5 gal its about a bucket and a half
:rollface:

 

[chemisfun11]

I use 5 gallon pails, some people use larger. If you want to be precise and use a larger container, clean out a 1 gallon plastic milk jug, mark the level of water on your container for reference and you'll know what point to hit each water change.

The larger the container, the larger the degree of error. That's why I like using 5 gallon pails

 

[Sk8r]

Don't toss the water you took out until you've added the new water: that way if you make a half a gallon mistake in the amount of new water you prepared, you can put a little of the old back in: a good reason for keeping even your waste buckets immaculately clean.
You can get good 5 gal buckets (food/drinking water grade) at any hardware store.
Also, match your salinity and temperature as closely as you can.
And look carefully at your tank before you start: have a plan where the hose will go. Turn off the pump: this way you don't end up draining the pumps in your sump. And don't let the inflow throw up sand.

 

[Debbie64]

Since you're using a Python to drain - I'm assuming it's the same thing I have which attaches to a faucet to create the siphon - you don't know how much water you're pulling out since it's mixing with the water from the faucet. I just drain my sump completely for a wc.

Rock and sand would change the overall volume, but this should be fairly close. If your tank is 20" high, that's 75/20" = 3.75 gallons an inch - roughly. 2 inches down should be about a 10% water change.

Unless you're pulling the water from your sump... In which case, do the tank volume calculation (length x width x height divided by 231) according to your sump depth.

Debbie

 

[YoungReefer06]

To determine how much water you want to take out ...LxW (of tank in inches) x H of water you are taking out divided by 231 give you gallons.

(LxWxH)/(231)=(X)gallons

So say you have a five gallon bucket of new saltwater, and you want to take out five gallons of water from the tank.

All you have to do if fill in the blanks of the equation to get how many inches you need to take out.

L=Length of tank (known)
W= Width of tank (known)
H=inches of water to take out (unknown)
231=(specail number lol)
X=number of gallon you ant to change=5

I hope this helps!

If you are not goog at math or dont understand give me you tank dimensions and how much water you want to change, and I will give you ho many inches to take out.

By the way I also use a python for water changes and this is how I figure out how much to take out.

Kyle

 

[YoungReefer06]

Sorry for saying the same thing LOL.

I didnt read Debbies post before I replied, my fault.

Kyle

 

[IslandCrow]

After incorrectly estimating too many times how much water I've taken out, I just make sure I mix more new water than I plan on using. That way, if I take out a little more than planned, no big deal.

 

[Debbie64]

That's OK Kyle. I won't hold it against you.

Debbie