TDS readings

[nightfire]

hey guys i tested a few things my tap water is reading 117ppm......publix water out of their 30 cent machine,atleast the one closest to me reads 35ppm...walmart distilled water 1ppm......ill check my rodo later after i clean it out some....btw those of you that are able to test ya tds of ya aquarium i'd like some feed back,mine is reading 685ppm now i know thats bad but is that normal? im not sure that reading a tanks ppm is even useful being that from the time you do a water change til you do another wont it always go up being that you have things that might die off,feedings and such....anyways i appreciate all comments and id like to thank jenifer for letting me use her tds meter for the weekend

 

[poolkeeper1]

Water Quality

Water Quality

hey guys i tested a few things my tap water is reading 117ppm......publix water out of their 30 cent machine,atleast the one closest to me reads 35ppm...walmart distilled water 1ppm......ill check my rodo later after i clean it out some....btw those of you that are able to test ya tds of ya aquarium i'd like some feed back,mine is reading 685ppm now i know thats bad but is that normal? im not sure that reading a tanks ppm is even useful being that from the time you do a water change til you do another wont it always go up being that you have things that might die off,feedings and such....anyways i appreciate all comments and id like to thank jenifer for letting me use her tds meter for the weekend

A better way to test your tank would be to test Nitrate and Phosphate to guage the condition of your water. JMO
Bill:thumbsup:

 

[nightfire]

if i did that i'd be shocked lol,also tests from my rodi will have to wait,the waste water is coming out fine but the pure side is not.....seems like no water id getting to my di.....dont know why

 

[poolkeeper1]

The Membrane may be shot, not letting any water get through it. If it sat dry for a long period of time it most likely no good. JMO
Bill

 

[nightfire]

good idea,ill try pulling it apart and seeing whats going on,either way i was gonna try to get a new one this comming month anyway,hey bill and others my restrictor says 450 flow is that good or what and what size membrane is that good for,i was gonna stick with filmtec 75gpd or lower since i see those have the highest rejection rate

 

[fishdoc11]

Tank water should have a high TDS as it has a lot of things dissolved in it.....like salt

 

[Jennifier615]

Yeah mine ran 6.7 when I got it and salinity and what not was all jacked up, now it's about up to 8.7.

 

[nightfire]

hey guys/gals i took my rodi apart and saw nothing wrong,put it back together and still didnt work, here is a pic of the end of my membrane canaster where the one on the right is for waste water and the one on the left runs to the di unit,now i'vve tried blowing through that end and nothing at all,it seems blocked up,am i supposed to be able to have air pass through it since water comes out it or is it fine and its a membrane problem

 

[nightfire]

also btw i took the membrane out and i can blow into and through the one on the left.....so is it that the one on the right is blocked somehow? i cant seem to undo the elbow from the chamber

 

[Pickupman66]

Mario, the clean water side shoudl have a little adjustment valve. make sure that is open. I would take the cartridge out, and blow thru all 3 lines. if you cannot blow thru one, it is blocked and you need to check it. the supply is the single line on one end, the waste is the outlet on the side of the other end and the good is the middle.

 

[nightfire]

i finally got the right side off and looked it has stopper or valve on the end of that elbow that goes into the chamber,it works i suppose because i switched the elbows and it worked ok,but if i put it back like the picture has it,it doesnt work...so maybe its a pressure issue and if thats so then well....i cant afford a booster pump.....maybe just need a new rodi unit and if thats so....again cant afford it so maybe ill be using publix water more then i first thought i would

 

[poolkeeper1]

Maybe the problem is the flow restrictor? A way to check would be to add a valve and take the flow restrictor out. This way you can regulate the flow through the unit to an exact 4-1 ratio, The more you restrict the waste side the more pressure you put on the membrane to force the water through. Then if possible you adjust the actual water pressure to 70psi with another valve (Gate valve) is best for this. To check this you run the unit and measure how much water comes out of each line until you get the 4-1 ratio @ 70psi then the unit is working correctly.
Bill

 

[Pickupman66]

Mario, try running it without the membrane.

 

[nightfire]

great ideas Bill and Pickup.......i think i have it working ok thought why would both lines be shooting a steady stream water,is it cause i need a new membrane? and ill keep testing my rodi,i'd hate to have to buy another being that there is a lack of money due to alll the hospital trips a month

 

[nightfire]

just an update....even though it is a steady stream of water coming out of the pure water line it is reading 42ppm which is better then the tap water which is 145ppm but again do i need to replace the membrane because it is shooting a stream? is that how i can tell its bad other then the obvious ppm of 42? thanks

 

[Jennifier615]

That millipore water inside our lab is to remove 99% of all water impurites and that TDS meter only registered 1ppm out of 100ml of water.

 

[nightfire]

i made a batch of water for a water change and its a pretty good ppm reading,though i do not know why the good water is flowing out in a stream like the waste

 

[Pickupman66]

Mario. you should have two streams of water coming out. the Waste water line should have a little valve on it that you can adjust. the tighter you screw that valve down, the more water goes thru the membrane. you shluld be 4 cups of waste to 1 cup of good. if you are off that ration, you will either wear your membrane out (less than 4:1) or waste too much water (more than 4:1).

 

[nightfire]

ii understand that from ya guys telling me but its running the exact same,meaning there is alot coming out of the pure side.....from many rodi units ive seen running the waste side is a syeady steam and the pure side are drips.....making that 4:1 like ya said.....if it helps ill post a vid tomorrow

 

[JTL]

I find it interesting that we test TDS and strive for zero with RODI but in the tank with salt it is in the 600 range. Freaked me out at first but I guess we are just trying to limit the bad solids. Even at that we are most certainly adding more not so good solids with the addition of food, LR ect. Hardly a perfect science and it makes me wonder if it is even necessary to test for TDS, let alone be concerned it the RODI reading is more than zero.