Topping off rimless tank

Cliving1

New member
So I don't have an ATO or anything, and since my tank has a huge surface area, I typically replace .25-1 gallon per day. I use distilled water to top the tank off, however after enough distilled my salt level goes down. Its not over night or anything but I notice a point or so every two weeks. Would it be helpful or harmful if I was to put reef crystals in my 1 gallon (equal out to 1.024) and use that to top off? Thoughts?
 
Do you have a mark or anything on the side of the tank that indicates when it's at capacity? Once your salinity is where you want it, as long as you keep the waters edge and this mark level your salinity should remain pretty stable IMO. The variation your talking about is really nothing to be too concerned about though, especially in that amount of time GL.
 
If at all possible get an ato. We have the same tank as we've discussed before. There is plenty of room in the stand. Do you have a sump?

I have the jbj on my 80 filling the sump and a hydor for my 40 without a sump by using an aqua lifter. Both have been great.
 
Thanks everyone! I have a piece of painters tape as my mark haha. Just easy for me and leaves no mark. I am just trying to see if it is good or bad if I put distilled mixed with salt in as my top off? Or should I just use distilled and watch my salt level?

Marchillo, yes we have the same tank. I am curious how yours is doing the last pics I saw you had a great setup and was very jealous of your lighting haha. I probably should invest in an ATO, just trying to get the financial advisor to support that investment.
 
You are fine making saltwater from distilled water and then using that (or any other saltwater you have on hand) to top off a tank in order to raise your salinity.
 
Yes it's fine, but as mentioned, you should probably figure out where your salt is going...that shouldn't happen.
 
Ok, thats what I figured, thanks thegrun.

Brian,

From my op, if I put in lets say max 1 gallon a day for 2 weeks, thats 14 gallons of "non" salted water. That would dilute my tank. Unless I know nothing about chemistry (at this point I hope I know some). Does that make sense? I would think adding distilled constantly would do that.
 
Ok, thats what I figured, thanks thegrun.



Brian,



From my op, if I put in lets say max 1 gallon a day for 2 weeks, thats 14 gallons of "non" salted water. That would dilute my tank. Unless I know nothing about chemistry (at this point I hope I know some). Does that make sense? I would think adding distilled constantly would do that.


No. When water evaporates, only the pure H2O evaporates. The salt stays behind. If you never topped off a bowl of saltwater, eventually you would have a bowl of dry salt.

So when you say your salt is going down...are you testing that or assuming that?
 
The water you are replenishing is evaporating water which is pure water. So when evaporation happens the salinity creeps up, when you top off you bring it down. The idea is that you have to fill exactly or as close possible to as much that had evaporated. If you put more then you're diluting. That is why everybody said about an ATO and a mark in your tank. My guess is that your water changes are not consistent (i.e. taking out more salt water than putting in)

EDIT: What he said LOL :)
 
Thanks everyone! I have a piece of painters tape as my mark haha. Just easy for me and leaves no mark. I am just trying to see if it is good or bad if I put distilled mixed with salt in as my top off? Or should I just use distilled and watch my salt level?



Marchillo, yes we have the same tank. I am curious how yours is doing the last pics I saw you had a great setup and was very jealous of your lighting haha. I probably should invest in an ATO, just trying to get the financial advisor to support that investment.


I saw a jbj for $35 shipped in the sellers section.
 
Hey Brian,

Much better explanation of what you meant I misunderstood through the typing of what you meant. That makes sense based on what you say on evaporation. But to be funny...I have never topped off a bowl of of saltwater ;) not sure why I would either. But, I do 15 or 20 gallon (depending how many buckets I remember to bring) water changes monthly. I have a hydrometer which I rarely use anymore and a refractometer. I am not assuming, that can lead to bad things in this hobby. When I said that over two weeks it goes down a point or so, that is based off testing, I wonder though if my equipment is just off now...
 
Hey Brian,



Much better explanation of what you meant I misunderstood through the typing of what you meant. That makes sense based on what you say on evaporation. But to be funny...I have never topped off a bowl of of saltwater ;) not sure why I would either. But, I do 15 or 20 gallon (depending how many buckets I remember to bring) water changes monthly. I have a hydrometer which I rarely use anymore and a refractometer. I am not assuming, that can lead to bad things in this hobby. When I said that over two weeks it goes down a point or so, that is based off testing, I wonder though if my equipment is just off now...


Yes. Something is fishy (haha, see what I did there). Unless you're manually removing water, your total salt shouldn't go down. So yes, 1 of 4 things is happening:
1. You have been manually removing a decent amount of water (we forget about all the water we take for tests, acclimation, etc)
2. You have a slow leak somewhere.
3. Your refractometer needs calibration.
4. Your water change salinity was lower than your tank salinity.

The bowl of saltwater was for purpose of a simple explanation.
 
I do have a mix, I wonder do they go bad? Its definitely a few years old (College to be exact). I know your bowl scenario was an example just sounded like something you have done haha. I think at this point I am leaning towards refractometer being off. I dont think I remove unnecessary amounts during testing, I always ask the lfs to match my tank level, and dont have a leak (that I am aware of). SO, I guess this post could have been because my equipment is off.

Long story short- I dont need to add salt to my distilled, it is perfectly fine to top my tank off with?
 
I do have a mix, I wonder do they go bad? Its definitely a few years old (College to be exact). I know your bowl scenario was an example just sounded like something you have done haha. I think at this point I am leaning towards refractometer being off. I dont think I remove unnecessary amounts during testing, I always ask the lfs to match my tank level, and dont have a leak (that I am aware of). SO, I guess this post could have been because my equipment is off.



Long story short- I dont need to add salt to my distilled, it is perfectly fine to top my tank off with?


Yes. Assuming your salt level is correct in your water change water, you should never need to add salt to your top off water. Regarding the manually-removed water, I keep a 1 gallon milk jug with fresh saltwater that I use to replace water I take out for tests and acclimations.

One other thing for people without an ATO; make sure when you do your water change, you top off with fresh water an hour or so before you start. Otherwise, you're going to slowly increase your total salt across several water changes.

Consider: if you normally run 1.025 but you're short a couple gallons from evaporation, your water may be 1.026. Then you do a water change and land the water level back where you normally keep it. Now your tank might be 1.0255 (because you added 1.025 water to 1.026 water). Do that enough times and you will way overshoot.
 
Well I appreciate everyone's support and feedback! Thanks Brian you have cleared some things up for me. I guess at this point (since I had another post deciding between glass and net screen top). I need to invest in an ATO.
 
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You should not be using Distilled water as it might contain copper. R.O.D.I is best.
It is always a goo idea to recalibrate your refractometer, before and after use with R.O.D.I water. A..T.O are not that expensive and save a lot of time.
 
You should not be using Distilled water as it might contain copper. R.O.D.I is best.
It is always a goo idea to recalibrate your refractometer, before and after use with R.O.D.I water. A..T.O are not that expensive and save a lot of time.


Agree with point 1. On point 2, you're even better off using calibration fluid that's set at 1.025. Ideally you calibrate at/near the value you're testing for. Calibrating a cheap refractometer with RODI can have you off by several points when you get up in the seawater range.
 
I highly doubt now a days stills have copper lines. If I am wrong, that would be interesting. But I do understand your point on variation. For example, I work in supply chain in the food industry and you would be surprised what can pass as saleable to consumers.
 
Agree with point 1. On point 2, you're even better off using calibration fluid that's set at 1.025. Ideally you calibrate at/near the value you're testing for. Calibrating a cheap refractometer with RODI can have you off by several points when you get up in the seawater range.

Yes you are right. That's what Randy said in one of his articles. Calibration fluid is often hard to come by. I often take my refractometer down to the L.F.S to calibrate it. But their water and measurement could be out. Calibrating with R.O.D.I water is better than nothing.
 
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