ro/di - distilled -water change

A

AngelLeah1981

Reefing newb
Thanks for all your great answers in the last thread. :)

I was told I can just use distilled water instead of ro/di? ....just add distilled water to salt and mix to correct specific gravity and make sure the water temp is the same as the aquarium and then slowly add water into tank? How slow? Do I pour it into the sump/fuge instead of the main tank? How will I know what specific gravity to make the replacement water compared to the aquarium water? How do I know how much salt if any to add? Will I need a seperate heater just for warming the water change water up? How much does an ro/di cost? Do you mind telling me the process you go through when you do a water change in GREAT detail.
Thanks a lot.
Leah
 
some people heat the water to the temp of the tank, but that is not necessary in a tank larger than 75 or 90 gallons as the amount of water in the tank does not change temps so easily.

I am not as careful as other people in this forum with the way I do water changes, but I have not had problems in 3 years. I take my "clean water bucket" and fill it with RO water, add my salt and stir it with my hand until it disolves totally and until my specific gravity reaches about 1.023.

I then take out my siphon and suck out the water from my DT into my "dirty water bucket". I like to clean about the top 1/2 inch of sand when I do my water changes, but not deeper than that. I usually only target algae spots in the sand, tho.

I then dump my new water right into the DT from the "clean water bucket" and I am done. It usually takes about 10 minutes. It is that easy. None of this "letting it sit overnight with a heater and powerhead" for me. too much worI have never lost a fish or coral putting water directly into the tank. I don't dump it in fast though, I pour it at a controlled pace and I do aim for a spot that don't disturb corals, usually near the side of the tank.

-Doc
 
The specific gravity of the new water doesn't have to match the old water exactly.

Be sure to only use plastic containers for holding water. Put your new water in a plastic container and follow the directions on the bag of salt for how much to add. Put a powerhead in the bucket and let it mix for several hours, then test the specific gravity. If it's between 1.022 and 1.026, you're fine. If it's not, add more water or salt to get it in that range. I use a heater in my container, but like Marco said, it's not necessary if the temps are close enough.

Then you want to take out the old water from your tank (shooting for around 10% weekly is a good goal), then replace with the new water. I just add the new water straight to the display tank, not slowly, I just dump it in.
 
here's my process for water changes. I mix the new salt water in plastic 5 gallon buckets, drop in a powerhead, and let it mix 12 to 24 hours. I have found it works better to let it mix this long. it takes longer than you think for salt to fully disolve. for example mix up a bucket and check s.g. then let it mix overnite and check it again. the s.g. will probaly be a little higher the next day.
I dont use a heater because room temperature of my house gets it pretty close to tank temp. plus the small amount of heat produced by the powerheads probaly help warm the water a little too. then I use a turkey baster and blow off all the rocks. I let it all settle for a while, then siphon water out of the bottom of the tank, sucking all the junk off the sand that I can. then I pump the water back in using a powerhead, with a nylon hose attatced to it. I do this just so I don't blow the sand everwhere and knock over corals.
 
I also make sure the s.g. for the new water is as close as possible to the tank water. I also check ph, calcium and alk to make sure it matches the tank as well, this is to make sure there are no major changes in parameters after the water change. I usually don't have to buffer anything in the new water since I switched to a better quality salt mix. but, I you are using a salt mix that is defecient in anything, such as a low ph or alk. I would suggest bringing it up to the tanks parameters before adding the new water to your tank. just to keep from shocking any animals from a sudden ph change or anything.
 
oh, I allmost forgot. the distilled water from wal-mart is just fine to use. If you read the label it says it's purified by reverse osmosis, microfiltration, and deoinization.

the cost of ro/di filters vary. there are some cheaper ones on e-bay that several people here are using that cost about 100 bucks, shipped to you're door. then there are some very expensive ones. but most typically they cost between 100 to 300 bucks. hope I covered everything:)
 
fishbait said:
I also make sure the s.g. for the new water is as close as possible to the tank water. I also check ph, calcium and alk to make sure it matches the tank as well, this is to make sure there are no major changes in parameters after the water change. I usually don't have to buffer anything in the new water since I switched to a better quality salt mix. but, I you are using a salt mix that is defecient in anything, such as a low ph or alk. I would suggest bringing it up to the tanks parameters before adding the new water to your tank. just to keep from shocking any animals from a sudden ph change or anything.
Click to expand...

What's the best salt mix to use? I checked the water we use in our lab today and got 000 ppm for TDS. Is this good? It is RODI water.

~Reefy
 
0 ppm for TDS is perfect.

The best salt mixes (in my experience) are Kent Marine, SeaChem and Oceanic. I use all three of them (depending on what's on sale at the time) and like them all.
 
I used to buy my water from walmart or a local grocery store. 2 things made me buy a ro/do unit. 1 - i got tired of taking my containers to the store and filling them every week, 2 - I tested the water a couple of times to find the water high in phosphates which contributed a lot to my terrible aglae problem I had. If you buy a ro/di system it will pay for itself in the long run if you stay in the saltwater hobby. I bought this RO/DI Unit
keep and eye on ebay. I got a 50gpd 3 stage for like $120. As far as water changes I mix my water and Red Sea salt in a 5g bucket with a powerhead, and water heater. I also check my calcium, ph, and dkh prior to adding it to my system. I only have a 29g so keeping all those as close to my tank water if not higher is helpful so I do not change the water chemistry too much. Like biff said Kent, SeaChem and Oceanic are all great and i too look for what is on sale.
 
I got a 100 gpd 6 stage unit on Ebay for $60. It totalled $100 with shipping. I've recommended that particular unit to everyone who is looking to buy an RODI unit, and I've been really happy with it so far. I bought it from the Ebay store Pure Water Club.
 
I just have the wife pick up 5 gallons of the wal-mart brand distilled water when ever she goes(at least 3X a week).
 
I guess it all depends on what the TDS of the water going in is at. Anything below 50, IMO, is okay for your tank. You should invest in a TDS meter to check, I got mine on Ebay for around $20 I think.
 
Salt mix facts. There are really no bad mixes, or incomplete mixes, or mixes short of anything amongst the major brand names. There are different demands by different tank contents, and different needs due to differing qualities of water used to make your final mix. One major problem experienced by many people now is chiefly due to the nearly pure state of the water they are using which has been filtered through both RO and DIO filters. Not surprisingly most of those people choose to use mixes which have higher than natural ocean water levels of calcium and buffers. THe same result can be had through the proper use of Buffers used with mixes made close to natural ocean water. Some mixes have up to 30-40% more calcium than natural ocean water.
There is a huge amount of information available at this url and through links at this url. There are both scientific tests and analysis and the observations of well known major marine and reef book authors who are primary contributors to the knowledge base of this trade/hobby.
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fishbait said:
oh, I allmost forgot. the distilled water from wal-mart is just fine to use. If you read the label it says it's purified by reverse osmosis, microfiltration, and deoinization.

the cost of ro/di filters vary. there are some cheaper ones on e-bay that several people here are using that cost about 100 bucks, shipped to you're door. then there are some very expensive ones. but most typically they cost between 100 to 300 bucks. hope I covered everything:)
Click to expand...
Fish, Walmart is passing off Filtered water as distilled? They are nothing a like. With distilled water, the water is heated to a vapor (leaving behind the bad stuff), and then the water is condensed in a coil and the purified water runs out the coil as a fluid. The same way shine is made, and whiskey is distilled. Not at all like the RO water they are selling you. Distilled water is more energy intensive to make and therefore more expensive to use and/or buy. You should be getting it at no more than about 25 cents per gallon, tops.
 
First of all I just want to apoligize for not getting back to you. I have been without internet for a while. I changed companies for faster service and they took FOREVER to set up. sigh. Anyways, thank you all for all your answers.
What if the tank is missing water already from evaporation and I remove water, how do you know how much salt to put in the new water if you don't know exactly how much water is missing? Doesn't it leave salt behind?

I usually don't have to buffer anything in the new water since I switched to a better quality salt mix. but, I you are using a salt mix that is defecient in anything, such as a low ph or alk.
Click to expand...
Does buffering mean changing the ph? Do I need to buy a certain kind of salt if I use a ro/di??

Quick question:

My RO unit says:
Maximum TDS (ppm) 2000
Percent TDS removed (ppm) 75-92
Click to expand...
I guess it all depends on what the TDS of the water going in is at. Anything below 50, IMO, is okay for your tank. You should invest in a TDS meter to check, I got mine on Ebay for around $20 I think.
Click to expand...
What does this mean? It sounds like you're saying the ro/di is hooked up to your tank. I'm misunderstanding right?
 
Buffering is done by carbonate complexes that make up what is referred to as the marine waters alkalinity. The job of a buffer is to neutralize acids that would lower your pH. If you need to raise your pH you do not use marine water buffers. The chief chemical used to raise pH is sodium carbonate (bicarbonate of soda). I use Seachem Reef Buffer to raise pH. I wish the would change the name as it is not a marine buffer (and there is no such thing as a pH buffer) and makes things confusing to many people. Do not use Marine Buffer or Reef Builder to raise the PH they are used for adjusting and or maintaining marine water alkalinity.
Usually most salt mixes are sufficient in buffers, however there is always the possibility there is not enough buffer for a new tank and the huge amounts of acids produced in a new tank versus an established tank. There are issues like whether your water was well aerated before mixing your salt water mixture. The pH of your make up water has some effect, but if it was drinking water it should not be extremely low or high pH wise, unless you live in a desert climate where water is bizarre. You should always aerate your water before using it to mix marine water or even before use as top off water. An exception to this is water used to make Kalkwasser which should not be aerated. Yes salt is left behind when water evaporates. You need to replace evaporated water with water that does not contain salt mix. There are hydrometers and refractometers to measure the salt content of your tank water. Ideally water for a marine or reef tank should have a TDS of zero after filtering and before mixing. It should be as pure as you can make it with reason cost wise. Usually a cheap RODI system is enough . I believe Biffer knows where to buy them for around $100. I have never seen water come out of a water tap with a TDS of over 650, and usually anything over 400 or so is softened by a water treatment plant where it is adjusted to around 100-150. TDS is chiefly considered a reading for calcium hardness. RODI filters with carbon also remove chemicals and heavy metals. They do not appreciably remove bacteria. A RO filter is not hooked up to a tank in the aspect of it is not filtering water from the tank. Some people do hook up the output of their RO filter up to there tank with a float valve to add RO filtered water for top off water to replace water evaporated from tank.
 
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I use the mighty mite rodi setup ebay for about 100 dollars happy with it so far. I agree on the letting the water mix over night tho I have done the test for sg the same day as adding salt and after a night with a powerhead. Go buy some new 5 gal buckets and lids very cheap at lowes.
 
Evaporated water leaves salt behind. When you top off your tank for evaporation, use fresh water, not salt water. Only use salt water for water changes (when you remove water from your tank and replace it with new water).

My RODI isn't hooked up to my tank. It's hooked up to my sink. Tap water goes into the RODI unit (at a certain TDS) and comes out the other end, with a much lower TDS. I run a line from my RODI unit to containers that hold the water for when I need to use it.
 

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