How often do you have to change your water in your res?

Budley Doright

Budley Doright

Well-Known Member
TheChemist77 said:
it dependes on the rez size and how much your plants are taking in...ive found at flower onset with a 70 gallon rez i change it every 8-10 days going from half grow,half bloom week 1-3 of flower.. then weeks 3-6 i run full bloom nutes and once plants are taking in 5 or more gallons per day, normally from weeks 4,5,6and 7 i only top off without a rez change..then for the last week i clean rez and fill with general hydroponics klean for a 1 week flush...
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What EC are u running when just topping off? Why r u changing before flower but only topping up in flower? Just curious as I would have thought the opposite if topping up. I try not to top up at all but never tried doing a run by just topping and not refilling.
 
TheChemist77

TheChemist77

Well-Known Member
i top off with nutrient added,, not plain water.. my ppm at week 4 of flower is at around 900ppm, and by topping off with nutrient water i increase the ppm so by week 6 its up to 1,170ppm and week 7 final week of nutes i add kabloom to my gh maxi series and my ppm to 1900.. by simply adding mixed water to top off,, its much easier than changing the rez and when plants are taking up 5-10 gallons of water per day the rez is actually being changed with fresh top off water every 10 days or so..if my ppm should get higher than i like than i top off with plain water to bring the ppm down.. luckily ive never had problems with slime or algea, my rez is on the concrete basement floor and stays at a perfect 60-65 temp...no air pump needed in flood and drain, as the water pumping onto the table then dropping and splashing back down into the rez keeps the water super oxegenated.. i use a 700 gal per hour pump and the tray floods every 4-6 hours for 15minutes depending on how moist the rock wool is after 4-6 hours..
 
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STR8QU4D5

Active Member
Budley Doright said:
It would be nice if you could rig up a plastic barrel with a float to keep a supply on hand :).
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Yeah totally. Im thinking of buying one of those big 40 Gal garbage bins and just filling it up with water. That way ill always have some on hand and I won't have to wait last minute to fill up the res.
 
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noosphere

Active Member
STR8QU4D5 said:
Yeah totally. Im thinking of buying one of those big 40 Gal garbage bins and just filling it up with water. That way ill always have some on hand and I won't have to wait last minute to fill up the res.
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If you can source a 40-50 gallon storage tank that would be a good thing. I have a 50gal one (I also use it for a couple of salt water reef tanks, and I use an Italian steam cleaning device instead of household cleaning chemicals). For MAJOR simplicity and convenience install a float shutoff valve near the top of the tank hooking it up to the output of your RO system and install an "auto-shutoff valve"(cheap) at the end of the RO unit (important). Without the auto-shutoff you'll have to babysit the tank fill. It also saves money and improves your water quality.

Your RO filter membrane will last much longer if you drain the tank down low and then fill it all the way up. Short, frequent refilling is very hard on the membrane. A cheap shutoff valve makes that easy. If your RO unit can't keep up with your demand, every unit I've ever seen has the ability to piggyback RO membranes and double your output. This also improves the water quality and greatly reduces your waste water. A fine tuned single RO membrane system typically produces 4-6 gallons of waste water for every one gallon of filtered final product you make. I live in the high desert and water is expensive here.

My tank is a milky white translucent polyethylene plastic. I tried spraypainting it with dozens of coats of black paint but light still leaked light inside. I ended up wrapping it with the "black on one side"/"white on the other" light blocking plastic material you commonly find in hydro shops. You don't want algae growing in your storage tank from ambient light! If you go the route of using some sort of garbage can check into the plastic it is made from. Some colors/kinds can leach chemicals into your water. Last time I looked Rubbermaid had good info on what colors/types were "food safe". They make no mention of lung safe :)

Last three things...
(1) If you want zero ppm RO water - investigate adding a filter canister with de-ionization resin downstream from your RO membrane. This will bring your output down to 0ppm.
(2) If you're using "city" water, call your water department and ask if they use chloramine in their treatment process. If they do, consider incorporating a chloramine carbon-block filter upstream of your RO membrane. Chloramine hammers your RO membrane(s) and it is nasty stuff. It makes water treatment cheaper and more and more govts are using it. It won't simply dissipate over time like simple chlorine. It makes it thru membranes.
(3) If water quality is important to you research RO system optimization. A website that has a lot of good info is called BulkReefSupply.com. They have their own reasonably priced brand of components and have a number of informative videos on the subject. Perfect water is important in the reef tank hobby.
 
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bird mcbride

bird mcbride

Well-Known Member
For F&D systems it is best to swap out the res every five to seven days, depending on the amount of water the plant(s) are using per every 24 hour shift. The res gets topped up with plain water every 24 hours.

I use dolomite lime to set the PH at 5.5 at the start. Do the fertilizer first then the PH. Set the fertilizer at 1/6 per gallon of water as outside directions for soil on the fertilizer package(s).

I use the spent budder res water on all green, mothers, clones etc drain to waste or wherever. I like the 2.5 gallon jugs with caps. I don't airate the water in the green room but if you want the jug can be used to airate by filling the jug about half way and give it a good shaking. The moms are on timed drip feeders and a pump up sprayer for the clones and foliar feeding with res water and fresh water as needed.
 
Budley Doright

Budley Doright

Well-Known Member
Well I'm not sure I agree with topping but if it ain't broke don't break it :). As for ease, I empty the Res which takes 3 min by opening a tap, then 3-4 minutes to fill and add my 4 things at the same amount every time depending on stage. But like I said if it ain't broke don't break it lol. If it was a larger grow then economic concerns would be involved I guess.
 
S

STR8QU4D5

Active Member
noosphere said:
If you can source a 40-50 gallon storage tank that would be a good thing. I have a 50gal one (I also use it for a couple of salt water reef tanks, and I use an Italian steam cleaning device instead of household cleaning chemicals). For MAJOR simplicity and convenience install a float shutoff valve near the top of the tank hooking it up to the output of your RO system and install an "auto-shutoff valve"(cheap) at the end of the RO unit (important). Without the auto-shutoff you'll have to babysit the tank fill. It also saves money and improves your water quality.

Your RO filter membrane will last much longer if you drain the tank down low and then fill it all the way up. Short, frequent refilling is very hard on the membrane. A cheap shutoff valve makes that easy. If your RO unit can't keep up with your demand, every unit I've ever seen has the ability to piggyback RO membranes and double your output. This also improves the water quality and greatly reduces your waste water. A fine tuned single RO membrane system typically produces 4-6 gallons of waste water for every one gallon of filtered final product you make. I live in the high desert and water is expensive here.

My tank is a milky white translucent polyethylene plastic. I tried spraypainting it with dozens of coats of black paint but light still leaked light inside. I ended up wrapping it with the "black on one side"/"white on the other" light blocking plastic material you commonly find in hydro shops. You don't want algae growing in your storage tank from ambient light! If you go the route of using some sort of garbage can check into the plastic it is made from. Some colors/kinds can leach chemicals into your water. Last time I looked Rubbermaid had good info on what colors/types were "food safe". They make no mention of lung safe :)

Last three things...
(1) If you want zero ppm RO water - investigate adding a filter canister with de-ionization resin downstream from your RO membrane. This will bring your output down to 0ppm.
(2) If you're using "city" water, call your water department and ask if they use chloramine in their treatment process. If they do, consider incorporating a chloramine carbon-block filter upstream of your RO membrane. Chloramine hammers your RO membrane(s) and it is nasty stuff. It makes water treatment cheaper and more and more govts are using it. It won't simply dissipate over time like simple chlorine. It makes it thru membranes.
(3) If water quality is important to you research RO system optimization. A website that has a lot of good info is called BulkReefSupply.com. They have their own reasonably priced brand of components and have a number of informative videos on the subject. Perfect water is important in the reef tank hobby.
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Great information! Thank you. Can you direct me to some examples, like links, videos etc so I can get a better idea of how to do this stuff? It would be very much appreciated!
 
N

noosphere

Active Member
STR8QU4D5 said:
Great information! Thank you. Can you direct me to some examples, like links, videos etc so I can get a better idea of how to do this stuff? It would be very much appreciated!
Click to expand...
Try this for link for some video and links to both the float valve installation and auto-shutoff:
https://www.google.com/?ion=1&espv=2#q=Installing+float+valve+in+storage+tank+for+RO+water

But for the auto-shutoff install I would check the site where you got your RO and they will most likely sell the valves and have the install info. Both bulkreefsupply.com and spectrapure.com are well respected RO sellers. Their support is good and can answer any questions you might have.

You might also consider one of these meters as it will monitor the ppm both coming out of the RO membrane and after the deionization filter if you install one of those (they also sell single function meters if you don't add a deionization filter). They also sell this inexpensive tubing cutter that is pretty nice to have around the house (a straight cut, that hasn't crushed the tubing is pretty important for preventing leaks on the little 1/4" tubing that is used on every RO unit I've ever seen).
 
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JJARTS

JJARTS

Member
I change it every week , first because after the second week the plants eat more and I have to put everyday more water to compensate the level, I have a 45 gallons reservoir that I fill to the top when start my week, and next day when the lights go on, the tank is 3/4 full, so when I check de mix, ppm are high and ph low, so I just add some plain water to put the mix balanced like new, plain water low the ppm and raise de ph with not need to ad nothing...and at the same time raise the level of the tank, I never add nutrients or ph busters to it, (ph if need it, but never happen) I keep it in that way 6 days, after it, i waste it and I run one day with just water, that water day I use to add any fungiside or incepticide or peroxide or sm-90 or all, I try to no mix the poison with the food this is why I use them in the water day every week, that day I didnt fill the reservoir to the top, I just put 15 or 20 gallons so I dont have to use a big amount of products that I will be waste them next day...I run the pump all the time while lights are on, I build my system myself custom acording to the area I have... the mix is running all the time, go to the plants that are in a clay mediun by a pvc pipes and feeders, pass pass through the clay and fall in a chanel under the 3.5 bucket and by gravity return to the reservoir that is under the chanels, and the pump puting it back to the plants and so on, never stop until lights go off, so the mix keep moving and fresh...I never add nutrients to the mix after the new food, nutrients are stick in the mediun and water clean it back. That water day I put the plain water and the ppm is around 300 but in few minutes that raise to 600 or 700 because the salt that remain in pipes and in the clay itself, this is why i didnt add anything after the first day of the week, just water...
Im cuban and my languaje is spanish, so I apology for my english and any inconvenience that it could cause or mistake I could be made... thank you.
 
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Scottmurphy12

Member
I change mine at the end of the perpetual cycle which is 9-10 weeks as the reservoir is 3 200 litre butts that constantly recirculate between each other and the water chiller. Essentially a modular flood and drain.
I know this isn't good practice but it would be too expensive to change the water every week I just add nutrients pro rata every time I top off. Plus they never show any deficiencies
 
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