Slightly Odd Question On Filters....

[Bob Sanders]

I installed a second set of filters (with back-washing ability). These are actually whole house water filters which offer a choice in filter types (3 filters have been installed in parallel to avoid flow restrictions).

First with the choice in filter cartridges.... I can filter down to 1 micron if I wish, (right now I'm using 5 micron filters) so I guess the question is how much filtration is good versus how much is simply 'excessive', and/or hazardous in having the ability to filters out the various chemicals REQUIRED?

Second, I also have the option of sliding in a chlorine/taste cartridge in if I wish. Now it would seem rather silly to be adding chlorine topside while removing it below with the filters but none the less let's say for some crazy reason I needed to do this..... would a chlorine filter also filter out the bromine?

(and yes.... I do have a separate filtration/heating loop with a 24 hour operating pump)

[reeffreak]

I installed a second set of filters (with back-washing ability). These are actually whole house water filters which offer a choice in filter types (3 filters have been installed in parallel to avoid flow restrictions.

First with the choice in filter cartridges.... I can filter down to 1 micron if I wish, so I guess the question is how much filtration is good versus how much is simply 'excessive'?

Second, I also have the option of sliding in a chlorine/taste cartridge in if I wish. Now it would seem rather silly to be adding chlorine topside while removing it below with the filters but none the less let's say for some crazy reason I needed to do this..... would a chlorine filter also filter out the bromine?

(and yes.... I do have a separate filtration/heating loop with a 24 hour operating pump)

If I am hearing you correctly, you are using a drinking water purification system as part of a hot tub filtration system? If so, understand that a whole house system is designed for a single pass application, it is not going to work for very long on a hot tub.. Here is some math... 10k gallons/month whole house usage, 6 month life of these filters = 60k gallons life purifying mostly clean water. Your 24 hr circ pump system, guessing @ 3 gallons / min would move the equivalent water through these filters in 333 hours, or exhaust and/or clog the media somewhere around 14 days. You are trying to use a filter technology that just isn't appropriate for the application.

Regarding your chlorine filter- that is a carbon block filter, which would capture organics, including bromine or most other sanitizers. Very bad idea there. You will quickly exhaust the media fighting sanitizer levels topside, then the filter will be doing nothing but restricting flow.

What is wrong with built in / standard filtration in your tub?

[Bob Sanders]

Well, you're kind of forgetting the fact that in a house application fresh unfiltered water is being filtered which would kill a filter faster while in a hot tub the SAME water is being filtrated.... less crap.... longer filter life. Not withstanding as already stated, backwash ability has been built in and if backwashed daily that in itself will GREATLY extend the life. I expect to get at least 3 months out of them if back washed properly (with exception to the 1 micron filters are not the greatest for backwashing.... which is why I'm using 5 micron right now) And to top it all off... the filters are about $4 a piece.

If I am hearing you correctly, you are using a drinking water purification system as part of a hot tub filtration system

Not drinking water PURIFICATION. That would entail the use of ceramic cartridges (or similar). These are normal whole-house filters. (Three have been installed in parallel)

hours, or exhaust and/or clog the media somewhere around 14 days

Well... we'll find that out in 13 more days I should point out though that I use these same filter systems (2 in parallel) at the cottage to filter untreated lake water... and they last about 1/2 the summer.... and that's without backwashing.

You will quickly exhaust the media fighting sanitizer levels topside

Yes... I understand that (as already stated). The question is however would they things filter out bromine? (I'm assuming so since they filter out chlorine)

What is wrong with built in / standard filtration in your tub?

The price for these filters are $4 each for starters. Secondly... you can pick them up just about any hardware store. Third... I have a wider variety of choice in cartridge types. Forth.... they have the ability to do a better job.

[waterbear]

You are also forgetting flow rates. The flow rates in your tub are much higher than the whole house filters can handle. Also, carts do not backwash well. You would do better taking them out and hosing them.

[Bob Sanders]

You are also forgetting flow rates. The flow rates in your tub are much higher than the whole house filters can handle. Also, carts do not backwash well. You would do better taking them out and hosing them.

You can take them out and hose them once a week or so. The back wash is there only for fast and simple daily cleaning. Flow rates are fine with 3 in parallel and these are not connected through the main pumps. I have an independent "maintenance loop" complete with its own pump which runs 24/7 for heating, ozone and filtration so they do not interfere with normal hot tub usage.

[reeffreak]

Your initial question and follow-ups reveal that you are either unaware of, or ignoring the significant engineering and design differences between tap water and pool/spa filtration concepts.

So I say go for the carbon block filter. It removes bad stuff from your tap water, so it must be better for your spa. And regarding your filter rating... 10 micron is good. 5 micron is better. 1 micron is best. Find the most effective filter you can get your hands on. If there is a 0.1 micron cartridge that will fit your cans, that would be ideal. Be sure to add a couple of cans of deionizing resin to the system to bring the TDS of your water absolutely to zero to have the most effective filter possible. And a can or two of dessicant will help too.. Because nothing in your system will remove that pesky di-hydrogen monoxide that even the best water filtration technologies won't get. Inhale a cup or two of that stuff and it will kill you.

Be sure to post back results.

[waterbear]

Your initial question and follow-ups reveal that you are either unaware of, or ignoring the significant engineering and design differences between tap water and pool/spa filtration concepts.

So I say go for the carbon block filter. It removes bad stuff from your tap water, so it must be better for your spa. And regarding your filter rating... 10 micron is good. 5 micron is better. 1 micron is best. Find the most effective filter you can get your hands on. If there is a 0.1 micron cartridge that will fit your cans, that would be ideal. Be sure to add a couple of cans of deionizing resin to the system to bring the TDS of your water absolutely to zero to have the most effective filter possible. And a can or two of dessicant will help too.. Because nothing in your system will remove that pesky di-hydrogen monoxide that even the best water filtration technologies won't get. Inhale a cup or two of that stuff and it will kill you.

Be sure to post back results.

+1

[Bob Sanders]

So I say go for the carbon block filter.

With due respect... you need to read a bit more carefully. No one said I was going to use a carbon filter. The question was (for the third time) will it remove bromine and not just chlorine? Placed in a PRACTICAL situation if you so seem to desire.... say I slip up one day and put too much bromine or chlorine in the tub. Might I be able to use one of these filters to remove the excess?

Your initial question and follow-ups reveal that you are either unaware of, or ignoring the significant engineering and design differences between tap water and pool/spa filtration concepts.

And which difference have I not addressed??

As for the filter system itself working (with a 5 micron filter)... it IS. It's working just fine. Flow rates are fine... filtration is fine, water clarity is fine. No fires, no overheating pumps... none of that rubbish. I am MORE than satisfied the filters are working as they should (better than a standard $40 or $50 tub cartridge)

[Spa_Guru]

Sounds like a lot of work to fix what isn't broken.

[Bob Sanders]

Sounds like a lot of work to fix what isn't broken.

You mean clean water is a bad idea? If it removes more than what a standard filter removes (which it does)at a cheaper price then is it or is it not broken to begin with?

[Spa_Guru]

Plain old fashioned polyester spa filters have been keeping water clear for decades, and chlorine has been killing the germs safely for a century.

[Bob Sanders]

Plain old fashioned polyester spa filters have been keeping water clear for decades, and chlorine has been killing the germs safely for a century.

And the good ole fashioned NTSC analog tv signal with the 4:3 cathode ray tv has been around for quite some time too..... so what's your point?

[waterbear]

So I say go for the carbon block filter.

With due respect... you need to read a bit more carefully. No one said I was going to use a carbon filter. The question was (for the third time) will it remove bromine and not just chlorine? Placed in a PRACTICAL situation if you so seem to desire.... say I slip up one day and put too much bromine or chlorine in the tub. Might I be able to use one of these filters to remove the excess?

Your initial question and follow-ups reveal that you are either unaware of, or ignoring the significant engineering and design differences between tap water and pool/spa filtration concepts.

And which difference have I not addressed??

As for the filter system itself working (with a 5 micron filter)... it IS. It's working just fine. Flow rates are fine... filtration is fine, water clarity is fine. No fires, no overheating pumps... none of that rubbish. I am MORE than satisfied the filters are working as they should (better than a standard $40 or $50 tub cartridge)

I suggest you look up dihydrogen monoxide!

[Bob Sanders]

I suggest you look up dihydrogen monoxide!

Why? Will it answer the question I have asked 3 times now? I guess I can assume no one here has an answer?

[reeffreak]

Bob, I answered your question in my very first reply. I don't know how you missed that in chopping every post up for a line by line rebuttal. I'll make it easier on you to quote me..

Yes, a carbon block filter will remove excess bromine based sanitizer from your water. I said that yesterday.

However, like the rest of this thread it is a solution looking for a problem.

I can tell you are a guy who likes to tinker. That is very cool. Your tinkering has solved a problem a problem for you- maybe your "problem" was the existing filter is busted, and your goal was to build a filter with parts from Home Depot. Maybe you had the stuff lying around and just wanted to play. Maybe you are trying to revolutionize water filtration technology in hot tubs.

Whatever your problem/goal was doesn't really matter, but don't come on the net trying to defend your brand new solution as better in every way.

You are taking an idea a couple of days old and confronting decades of industry best practice.

If this idea had mass appeal, the manufactures would be using this approach already. Because it's cheaper, better, easier, etc.. For some reason they haven't. We are giving you suggestions why.

Back to the carbon.. It is an inefficient, expensive way to do remove excess sanitizer.

You would be quicker and/or save $$ with a partial water change, or leave the cover off to let the sun get to it, or neutralize with sodium thiosulfate (or maybe even household peroxide- our chemistry experts would know).

Or you could just tee tee in your tub.

Good luck, I am back to lurking.

[Bob Sanders]

I can tell you are a guy who likes to tinker.

Thank you.

Yes... it's quite true... I do like to tinker and probably part of the reason I did this. The other part of course is that fact that I went to the store to pick up a new filter and they wanted $45 for one. Bare in mind this is about $3 in pleated paper glued together with a bit of molded rubber (or similar). Somebody sure is making a tidy little profit! Maybe that's why manufacturers haven't changed systems?

The system I now have uses MUCH cheaper filters that do a MUCH better job. Granted I have to use 3 in parallel to avoid flow restrictions, but even replacing 3 at a total of $12 is a heck of a lot cheaper.

And the back wash system.... it'll lengthen the filter life and pools use back wash systems so why not hot tubs? Mind you my hot tub is connected to the house and the filters are actually inside where there is a water supply which is of course already protected from the possibility of freezing so that makes a big difference.

Carbon filters? It was just a question of curiosity.... nothing more.

I'm quite surprised at the eruption of raw feelings this has caused. Not sure why people are so defensive over the issue. It seems when something different is tried. or even thought of... be it filters... chemicals.... what have you, people start talking about how the industry has survived this way for decades and are pretty insulted in the idea of some one not towing that line. Go figure!?!

[waterbear]

. The other part of course is that fact that I went to the store to pick up a new filter and they wanted $45 for one. Bare in mind this is about $3 in pleated paper glued together with a bit of molded rubber (or similar). Somebody sure is making a tidy little profit! Maybe that's why manufacturers haven't changed systems?

Bear in mind that cart filters are made of polyester, not paper, unless they are the ones designed to be thrown away and not cleaned and, to my knowledge, those are only used on Intex pools and whole house water filters. Seem like you didn't do your homework on this.

The system I now have uses MUCH cheaper filters that do a MUCH better job. Granted I have to use 3 in parallel to avoid flow restrictions, but even replacing 3 at a total of $12 is a heck of a lot cheaper.

Have you disabled the internal filtration or are you using it in conjunction with it. ANY supplemental filtration will imporve overall water filtration BUT if you have disabled the interal filtration you are now allowing unfiltered water to pass through the pump, wihc is NOT a good idea! I am going to assume the filters you are now using are paper and not polyester since they are so cheap.

And the back wash system.... it'll lengthen the filter life and pools use back wash systems so why not hot tubs?

If you were using a sand filter then fine. Cartridge filters on pools are NOT backwashed, only sand filters and some DE filters (but backwashing a DE filter is not a good idea for reasons I won't get into here since it is off topic. Bump type DE filters are not backwashed anyway. For that matter, sand filters on ponds and aquariums are backwashed but DE and Cart filters in these applications are not! Backwashing will not get a cart clean.

Seems like you didn't do your homework on this one either!

Mind you my hot tub is connected to the house and the filters are actually inside where there is a water supply which is of course already protected from the possibility of freezing so that makes a big difference.

Carbon filters? It was just a question of curiosity.... nothing more.

Carbon filters would soon be rendered useless if there is chlorine or bromine in the water and considreing the amount of organics in the water, given the samll size of the filter. consider that carbon is replaces every two weeks or so in aquairum filters, and it is about the same amount of carbon in a much smaller volume of water than in most hot tubs (not to mention the bacterial filtration that occurs in aquariums)! In house situations carbon filters are designes to remove tannins and possibly some odors from the water and adsorb small amounts of impurities from what is already considered "drinking water". This is quite different than the heavy load of "impurities" that is in your spa water.

I'm quite surprised at the eruption of raw feelings this has caused. Not sure why people are so defensive over the issue. It seems when something different is tried. or even thought of... be it filters... chemicals.... what have you, people start talking about how the industry has survived this way for decades and are pretty insulted in the idea of some one not towing that line. Go figure!?!

I haven't seen anyone except you become defensive. You received quite a bit of feedback why people thought your idea was not a sound one and you have demonstrated that you do not really have enough knowledge of water filtration through your comments as I illustrated above!

I suggest you look up dihydrogen monoxide!

Why? Will it answer the question I have asked 3 times now? I guess I can assume no one here has an answer?

The reference to dihydrogen mononide was a tongue in cheek one , btw. I am curious if you got the joke.

To answer your question you "asked 3 times now":

I installed a second set of filters (with back-washing ability). These are actually whole house water filters which offer a choice in filter types (3 filters have been installed in parallel to avoid flow restrictions).

First with the choice in filter cartridges.... I can filter down to 1 micron if I wish, (right now I'm using 5 micron filters) so I guess the question is how much filtration is good versus how much is simply 'excessive', and/or hazardous in having the ability to filters out the various chemicals REQUIRED?

Filters do not filter out CHEMICALS, they filter out particulate matter. The smaller you filter the clearer the water BUT the faster the filter medium will clog and have to be replaced and also the smaller the media the higher the backpressure on the system and the slower the flow rate thought the filter. These last two factors are important to consider to avoid pump damage. Remember, whole house filters are usually designed for normal household water pressure of 45 to 60 psi and flow rates of about 5 gpm or less. The the flow rate and pressure in a spa is most likely going to be much higher. (and the wear and tear on your pump seals also from your homemade filter setup!)

Second, I also have the option of sliding in a chlorine/taste cartridge in if I wish. Now it would seem rather silly to be adding chlorine topside while removing it below with the filters but none the less let's say for some crazy reason I needed to do this..... would a chlorine filter also filter out the bromine?

It would filter out any halogen BUT given the amount of chlorine or bromine in your spa and the fact that it is constantly being added the carbon filter would be rendered spent and useless in a very short time to make is a useless additions. Anyway, if your intention is to switch to chlorine from bromine without a drain and refill it won't work. The filter will NOT filter out the bromide ions since they are DISSOLVED in the water nor will it remove any organic bromine (DMHD is the carrier in bromine tablets and tends to stabilize bromine in a similar way that cyanuric acid stabilizes chlorine but not to the same extent. It mainly keeps the bromine in a 'recyclable" form to be converted back into bromine sanitizer.) If you want to convert from bromine to chlorine you MUST drain and refill. Period. If you are just trying to lower too high a bromine or chlorine level (and it is really a too halogen level and not interference from MPS or ozone on testing) then adding peroxide or thiosulfate is a much faster and efficient way to lower the sanitizer level. Once again you have not done your homework!

(and yes.... I do have a separate filtration/heating loop with a 24 hour operating pump)

I hope that has finally answered your 'unanswered first question' which reeffreak did answer in his very first post!

I hope you carefully read what I have posted and do a bit more research into water filtration basics! Then you will understand why your whole house filters are not a good idea. They are throw away filters. Spa filters are designed to be cleaned. Your $4 a piece filters will soon become a very expensive proposition. A $45 spa filter should ast up to 5 years in a halogen system (that's $5 a year!) and 1 year in a biguanide system if they are properly cleaned monthly. (hosed off and soaked in TSP or automatic dishwasher detergent and acid washed ONLY when there is scale deposit present for halogen systems and using the proper proprietary filter cleaner for biguanide systems). Do the math!

If you want my opinion based on my knowledge and experience in not just pool and spa filtration but in 45 years experience in aquarium filtration (35 years of that in large reef tanks), Including many 'homebrewed" filters I would have to say FAIL!

[Bob Sanders]

I hope that has finally answered your 'unanswered first question' which reeffreak did answer in his very first post!

I hope you carefully read what I have posted and do a bit more research into water filtration basics! Then you will understand why your whole house filters are not a good idea. They are throw awaySpa filters are designed to be cleaned.

I hope you understand you haven't the faintest idea what you're talking about. I have used these filters systems (with 5 micron filters) for the last 10 years at my cottage to filter the lake water. I know them slightly better than you do.

[waterbear]

I hope that has finally answered your 'unanswered first question' which reeffreak did answer in his very first post!

I hope you carefully read what I have posted and do a bit more research into water filtration basics! Then you will understand why your whole house filters are not a good idea. They are throw awaySpa filters are designed to be cleaned.

I hope you understand you haven't the faintest idea what you're talking about. I have used these filters systems (with 5 micron filters) for the last 10 years at my cottage to filter the lake water. I know them slightly better than you do.

I hope you understand that insulting people is not a good idea. Also, you have no idea what my background or experience is so blanket statements like you just made are a bit uncalled for. However, you made it very clear that your experience with them is limited to using them on one cottage with 5 micron media. However, once again the GPM and flow rates are much different than in a spa and they are not under continuous use. Whole house filters receive intermittent use (unless, of course, you keep your faucets and shower running 24/7).

[waterbear]

This quote from another thread sums things up nicely!

You don't seem to understand that it is not my knowledge and experience that is being talked about. I've already admitted SEVERAL TIMES NOW that I have very little experience when it comes to discussing things directly related to spas.

[Bob Sanders]

I was going to leave this one alone... but since you brought it up...

It's been more than 2 weeks now and the filters are functioning great. No plugging, no excessive back pressure or anything of that nature. I did find that daily back washing was only required in the first week or so. After that I was able to cut it back to every other day. As for taking them out and washing... I've only done it once so far. I've only got the 5 micron filters in at the moment but it's all working well enough so that I may drop down to the 1 micron and see what happens (they're the same CHEAP price of 4$ each as the 5 micron so it's no great loss if they don't go as well)

[spawn]

Where does your backwash water discharge when you backwash? Do you manually open and close value or do you have electronically operated valves?

[Bob Sanders]

Where does your backwash water discharge when you backwash? Do you manually open and close value or do you have electronically operated valves?

Manual valves. The backwash goes to the house drain stack. (I have an indoor/outdoor hot tub and the filters are located in the basement next to the sewer stack).

[spatech (the unreal one)]

Your initial question and follow-ups reveal that you are either unaware of, or ignoring the significant engineering and design differences between tap water and pool/spa filtration concepts.

Based on this and another thread Bob started I'm not so sure he's interested in anything anyone else has to say even if its their area of expertise. I think he was just posting this expecting people to say "wow, that is great". Everyone else just doesn't seem to understand. I stopped on the other thread after a bunch of other people also tried to expalin how he was off base in his analysis yet he just stuck to the idea he was right and we were all wrong.

[reeffreak]

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