Water change and salinity stability

[Tease Aquatics]

Advise on how to keep your salinity stable when doing water changes?


little insight into my set up:
-I have a 50 gal reserve barrel I use to store RODI Water
-when I do water changes I shut off my return pump And use a vacuum hose to take water directly out of my display tank so I may clean the sand at the same time
-Then I usually add RODI to my sump and once almost full turn the return pumps back on.

my sump won’t hold enough water for me to completely fill the display tank back up so I have to do this circuit a few times ... return pump off, fill RODI to sump, return pump on till sump is drained, repeat.

 

[Jon Fishman]

Replace as much water as you remove with the same amount of saltwater at the same salinity level as the water you removed....... Is this a trick question?!

 

[Tease Aquatics]

Replace as much water as you remove with the same amount of saltwater at the same salinity level as the water you removed....... Is this a trick question?!

My problem is is that I’m using a vacuum hose and it’s going directly into a drain. If I were taking water out of the tank into buckets and had an idea of exactly how much was being removed it would be a bit easier to calculate how much to put back. Maybe I’m just making it to complicated for myself.

 

[Jon Fishman]

My problem is is that I’m using a vacuum hose and it’s going directly into a drain. If I were taking water out of the tank into buckets and had an idea of exactly how much was being removed it would be a bit easier to calculate how much to put back. Maybe I’m just making it to complicated for myself.

Yeah, use a 5g bucket or a brute on on a dolly and then dump. I siphon out with a pump connected to a hose, and then drop the same pump into a brute with new water and re-fill.

 

[stanleo]

My problem is is that I’m using a vacuum hose and it’s going directly into a drain. If I were taking water out of the tank into buckets and had an idea of exactly how much was being removed it would be a bit easier to calculate how much to put back. Maybe I’m just making it to complicated for myself.

Get a five gallon bucket and time how long it takes to fill it with the vacuum hose. Then, run a stop watch and stop when you have drained the right amount of water.

 

[AdamB]

Vacuum water into a measured bucket(5gal) that you can get from Lowe’s and monitor how much youtake out and Mark a line with a sharpie on both tank and sump to know when to stop on the amount you usually take out when you feel it up .. that’s what I do and works great. You can make a different colored mark in a inconspicuous area if you want to siphon a different amount out . Ie. 10% or a 20% water change

 

[SoggyNW]

If your sump is directly below you tank I would use a siphon to clean the sand directly into the filter sock just before changing it. I would then perform the water change from the sump so you can match the water level.

 

[Ranjib]

My problem is is that I’m using a vacuum hose and it’s going directly into a drain. If I were taking water out of the tank into buckets and had an idea of exactly how much was being removed it would be a bit easier to calculate how much to put back. Maybe I’m just making it to complicated for myself.

Why drain it directly and not keep it a temporary holding place where you can ensure a fixed volume. Even if its for just few minutes. If the volume is fixed. your salinity is dialed in. I know exactly how much I'll take out and exactly how much salt i have to add (2 big spoon and 1 1/3rd spoon for every 5G), to keep it dialed at 1.26.
Some time i take out more than I should, mostly because im chasing some gunk or dirt, and thats cool too, I just pour back the additional amount. From the top of my holding place, where the water is at least free of large heavy dirts.

 

[sharpimage]

You need to add premixed saltwater back into the tank. not just ro/di

 

[Tease Aquatics]

I don’t use buckets because it’s a long walk across carpet to dump them but that sounds like what I need to start doing. Thanks for the advise everyone.

 

[Nano427]

You could also use the standard 5 gallon water jugs to drain into, so you can cap them while carrying them across your house. Or I guess you could try lids on the 5 gallon buckets. Either way, in my opinion, water changes should be measured out in gallons so you can keep track of the results. I wouldn’t recommend more than 20% unless you’re trying to fix an emergency situation.

 

[Ameer214]

You need to add premixed saltwater back into the tank. not just ro/di

Yeps...OP, is the rodi that you are adding back in have salt mixed in? That may sound obvious, but just want to confirm.

 

[Mastiffsrule]

Evening

First off #WelcometoR2R . Glad you’re here.

Just FYI. You should always first check DT salinity . Do you have an ATO or other method of keeping it constant.? Once you know salinity then mix new water to match tank water at salinity and temp . If you use Rodi to fill you are diluting or dropping SG.

I mark the current water line then shut down my pumps . Make sure you have enough room in the sump to hold the back flow. This is also good idea in case of power. Once all the water settles you can mark a level in the dt at water line. You can then drain and measure the amount drained to the amount you need to put back in. The first few times will take adjusting. One you have the water level marked on the tank and sump you should know how much to drain and replace.

After I drain mine to level marek on the Dt I fill back and kick on the pumps just short of my lines just to be sure I don’t overfill

 

[Goodair]

I took a sharpie and marked the waterline with pump off, and some additional markers I know that I cant siphon anymore water out (wc barrel holds 30g).
Marks are on the back corner so you don't even notice them.

It's been very useful as originally I'd siphon out too much water while cleaning substrate and then the pumps would have to stay off for a longer period as more water got preped.

 

[AdamB]

I took a sharpie and marked the waterline with pump off, and some additional markers I know that I cant siphon anymore water out (wc barrel holds 30g).
Marks are on the back corner so you don't even notice them.

It's been very useful as originally I'd siphon out too much water while cleaning substrate and then the pumps would have to stay off for a longer period as more water got preped.

Same here. Making a mark on sump and display inconspicuously to know the gallon amount has worked great for me . Very simple.
I use python hose to siphon water outside house and then pump my mix to tank 30’ away. No Mess like the old bucket way of doing things ..

 

[krbshappy71]

"Once you know salinity then mix new water to match tank water at salinity and temp . If you use Rodi to fill you are diluting or dropping SG."
@Mastiffsrule Pardon my jumping in, but I had a stupid question on this, how will I get the temp to match? Am I nuking it in the microwave? Should I be having a separate tank heater for water change buckets?
Thanks in advance, no tank yet still learning.

 

[DanH86]

I use a spare tank heater, drop it in my barrel for a few hours before I do the water change. Always good to have spares in case of a failure and in this case they get put to use - powerhead for mixing fresh saltwater, heater for heating it.

 

[mike550]

I don’t preheat the new water going into the DT for a couple of reasons. First, the temp difference between my “unheated” water and DT is about 5-7 degrees. Second, the volume change is around 15-20%. So I don’t think it has significant impact on overall tank temp. Simple math on 20% water change with 5 degree difference would be around a 1 degree swing.

 

[krbshappy71]

Ah! Ok thank you, easy enough to have one on hand, and now I know to check first to see how different the temps and salinity are from the DT.

 

[Mastiffsrule]

"Once you know salinity then mix new water to match tank water at salinity and temp . If you use Rodi to fill you are diluting or dropping SG."
@Mastiffsrule Pardon my jumping in, but I had a stupid question on this, how will I get the temp to match? Am I nuking it in the microwave? Should I be having a separate tank heater for water change buckets?
Thanks in advance, no tank yet still learning.

Hello @krbshappy71,

First, always jump in, start your own thread, PM. Anything is acceptable if you have a question, and none are stupid. Obviously don’t want to hijack a thread in a totally different direction , but a question about the topic is no problem.

@DanH86 mentioned a spare heater and pump are great things to have. They don’t have to be high end, just sufficient to do the job. I use both when it comes to water changes. I fill bucket with RO, drop powerhead or pump in fo circulation and then add salt. Once salt is dissolved I put in heater. And as he said, always good to have back ups.

I agree with what mike said in general, but there is another consideration. While the temperature shift may be small, that is a shift after the water has been dispersed. When first adding the colder water it will take a moment to disperse and mix in. There is a possibility if you pour the colder water in the area of acro or sensitive organism it may be an issue. Matching temp is more of a safety thing than worrying about shifting the overall tank temp.

Hope that’s got it.