YBeNormal

Ditto. I might have even learned something from your post. Probably not, but I feel smarter!

Thanks guys. I really should break out a better camera, but it's hard to do that when you are covered in sawdust and on a roll. I feel the same way. This monster is taking up a lot of real estate in the garage, er, I mean woodshop! The stand will be 36x72x30. It only has to fit through the garage door opening at my place. Getting it into Roni's house might be another matter though! The workshop has grown over the years, with me sleeping on the couch for a few nights after each major tool or machine purchase. It's my place of escape though and keeps me out of trouble.

Algae will store nitrates and phosphates as it grows, helping to explain the zero readings you are seeing. The other issue is that home test kits are not entirely accurate and most will not display very low readings. If you have algae, you have nitrates and phosphates, even if they are not detectable in the water column using home test kits.

The stand build slowed to a halt while we discussed and researched some changes in the design of the facing, doors, and wood choices, but it's back on track now and progressing nicely. Hopefully the weather and my day job will cooperate this week and I'll be able to complete the outside face of the stand. In the meantime, here are some recent pics of the frame construction. I apologize for the iPhone pics being so grainy. Hopefully the iPhone 5 will have a much better camera than the old 3GS I am currently using! Built the basic frames for the top and bottom: Add the support posts: Cut and mounted the plywood inside the base: Added the top of the frame: Routed the back side of the stand and inserted the recessed plywood panel: And the frame is almost complete. I will add some short sections of 2x4 behind the top/front 2x4 (just for a little extra support), then have to do some minor filling of nail holes and sanding: I hand-picked some real nice walnut for the face and sides of the stand: The walnut was 4/4" lumber, rough on all 4 sides. I used the planer to smooth the top and bottom surfaces, to reduce the thickness to 3/4", and to annoy the H-E-double hockey sticks out of my neighbors this evening. The wood looks much better with a smooth finish. I hope to cut the walnut to size tomorrow and begin assembling the face frame before the weekend. More pics to follow!

Good point.

Right, this just helps kill the algae so you can remove the trapped excess nutrients through filtration, water changes, etc.

It should not hurt them, happens in nature all the time. There was a very long thread on RC a few years ago about turning off the lights for a few days each month. General consensus was that the corals actually seemed to thrive, with better color and polyp extension afterwards--not to mention a noticeable reduction in electricity costs!

The nitrates, phosphates, and algae are all related with the nitrates and phosphates causing the HA; the HA die-off releasing nitrates back into the tank (nitrates that started with feeding of course). It's frustrating, but will improve rapidly once you begin to get a handle on things. The high TDS after replacing all filter media is another matter. I mentioned that even new RO membranes can be defective and suggested that you check TDS from your RO output after changing the membrane. Even if the new membrane was bad though, the DI resin should have mopped up the impurities and left you with 0 TDS. I think the next step would be to verify that your TDS meter is functioning properly. Can you cross check it with another TDS meter from someone close by?

Yes, 150GPD should be sufficient for your needs, especially since you can prepare and store the water in advance of your needs. KATI DI-type systems could put out several hundred gallons per day. The resin will become exhausted quicker since you are not running it through an RO membrane first, but the resin can be recharged and reused several times (not sure how many). These systems are ideal for larger tanks and for people who live in areas with high water and sewer costs since there is zero waste water.

Bob, A very good friend of mine was diagnosed with brain cancer several years ago. The tumor was a branching type and had grown quite large before being noticed. She was given months to live and the option of a surgery that would either kill her or perhaps extend her life by a few months. Surgery took many hours with friends and family worrying the whole time. She recovered fully and is alive and well today--with no signs of cancer. While I'm saddened to hear what you have been going through, I'm very happy to hear that you are doing well and I hope you are around another 40 years (why settle for 20?) to continue telling everyone that life is worth living and worth fighting for! You and your attitude are an inspiration to everyone who knows you! --The other Bob P.S. I still have your blue storage barrel, the one you left here about three years ago after the frag fest. Let me know when you want it!

One company selling the large capacity resin chambers in the US is Ready Aquatics. Here is a link to the page with the 1-liter version. Links to larger versions are included at the bottom of the page. Description:

I'm not knocking BRS, just stating that they are resellers of products, not experts in the field of any of the products they sell other than maybe the maxi-jet retro kits they sell, and even those are derivatives of the work of someone else that they then capitalized upon. I'd prefer to get my advice on filtration from AWI, TFG, Spectrapure and some of the other companies specializing in water filtration and/or to do lots of research myself (something I have done a lot of over the years). Good idea about using two DI chambers, but you still have to be very careful trying to stretch the DI resin too long. True, the second chamber should pick up the load once the first chamber is exhausted. Unfortunately, the anion and cation resins in a mixed-resin system may not become exhausted at the same time. Also, the resins work by capturing charged particles and when they are at or near being exhausted, they will begin to release impurities with a lower charge in favor of other impurities with a stronger charge. Phosphates have a relatively low charge and are one of the first impurities to be released (or not filtered in the first place) in this process. You typically will not notice this until you end up with a major HA outbreak or something similar, and then it is too late. I learned to replace the resin before it was fully exhausted and saved myself lots of headaches by doing so. Resins aren't cheap, but they aren't too expensive when purchased in bulk.

The AWI Typhoon units, and many others I've seen, have a fourth canister mounted vertically just like the sediment filters. You can also purchase extra housing units and wall mounts to add additional sediment or DI chambers. IRT having dual DI chambers to decrease time required to produce water, that won't really help since the output of the RO membrane is the limiting factor. The second DI chamber will only allow you to go twice as long before having to replace all of the DI resin. Since the first DI chamber should filter out all impurities until the resin is exhausted, the second chamber will also help guard against either the cation or anion resin in the first chamber becoming exhausted and allowing impurities to slip through. If you want to decrease the time it takes to produce RO/DI water, you will either need to go with a 100GPD membrane (being careful to match the flow restrictor and to get a high quality 100GPD membrane with a high reject rate), double up the RO membranes, or both. To be honest though, I would purchase a unit with a single, high quality 100GPD RO membrane and maybe add a second or dual DI chamber, then use one or two large Brute trash cans to store the purified water. If you want high output and don't mind spending a little extra, TFG offers a 150GPD unit with two RO membrane. Yet another option for this or any other system would be to have one chamber for cation resin and another for anion resin. This would not increase output but would allow you to easily and cheaply recharge and reuse exhausted resins, saving money over the long term. Finally, you could get the best of all possibilities by using only sediment prefilters and large capacity chambers for anion and cation resins, eliminating the RO membranes entirely. This would give you high output and zero waste water, but with a large investment upfront for the large resin chambers and the resin itself. Anthony Calfo posted something recently about a company selling these large acrylic resin chambers in the states. I'm sure I could find a link or could get the information from Anthony if you are interested. You could DIY the large resin containers using PVC, but would not be able to see the resin color changing and would have to monitor the output closely to know when the resin is exhausted.

TFG and AWI are both well established companies that specialize in water filtration products and they tend to give very good advice. BRS is also a good company with good prices, but it is basically a hobbyist reselling multiple products. The DI chamber in the picture could easily be mounted in a vertical position, so there is no need to replace it.

Looks good Roni! Personal preference maybe, but I would reorient the DI chamber and mount it vertically. My thoughts are that this minimizes chances of water being channelized through the resin. I noticed The Filter Guys also state, "For DI filtering we recommend full-size refillable vertical DI color changing resin cartridges and clear housings. Vertical housings offer superior performance with channeling being less of a problem."

I checked and I do have everything, including full sets of AWI particulate filters, RO membrane, refillable DI cartridges with resin, and extra resin refills. As I said, I'll sell them to you at AWI prices. Sediment filter pack: http://www.airwaterice.com/product/3PACK/3-Pack-Filters.html $19.95 75 GPD membrane: http://www.airwaterice.com/product/TW301812-75/FilmTec-Membrane-75-GPD.html $39.95 DI Replacement canister (and I'll throw in an extra refill: http://www.airwaterice.com/product/DICC/DI-Cartridge-Single-Color-changing.html $19.95 Let me know what you want and I'll have it ready for you. We're heading downtown for a couple of hours but will be home after dinner. I'll PM my address and phone number. Bob

I think you have a good plan. First, other than a few proprietary filter units, all units use standard filter sizes so you can buy from just about anywhere and they will work in the AWI units. When measuring TDS, make sure you are measuring straight out of the unit, preferably in a clean glass. Plastic storage bins and the like will cause an elevated TDS reading sometimes and this is not necessarily a bad thing. I think I have at least one full set (RO membrane, carbon and particulate filters, and resin) in my spare storage. Since my tanks are not in use, I'd be more than willing to sell them to you at cost (no shipping charges, but you'd have to pick them up). Let me know if you are interested and I will verify that I still have everything. Since you know you have elevated phosphates, that would be the first thing to tackle and will probably go a long way to resolving your HA issue. Of course, nitrates will follow as the HA dies, so good filtration and water changes will be a must. Once you get the phosphates down, I'd turn the lights off for three days, even cover the tank to block all light if you can. It won't hurt the corals, in fact, corals often color up even better after a short period of darkness. I guess this simulates a stormy period in nature or something.

I think the consensus is that it is a good idea to buy an RO/DI unit and that you should consider a used one, being careful to factor in costs of replacement filters and membranes. The advantage to going that route is that you might save a few bucks. You should also consider buying a new one. Advantages to buying new are that you get exactly what you want (or are willing to pay for) and the unit is usually covered under some sort of warranty. There is no single right answer. Weigh your options and go with the route you feel most comfortable with.

There *is* silicon under the trim on both the top and the bottom--and lots of it. You have to carefully cut through as much of it as you can. I use one of the long, thin retractable razor knives to do that. Once you have cut through and removed as much of the silicon as possible, you have to carefully pry the plastic away from the glass by hand, pulling a little in one area and moving around the tank until it comes off. I also recommend removing the bottom trim first. I've had real good luck when I've done this, but the plastic will crack or break if you try to rush the process. Good luck!

Besides being a sponsor, AWI has a lifetime warranty on the stuff they sell--and they stand by their warranty!

I live in Manassas, have some scrap acrylic, and can make the cover for you or help you make it yourself. Your choice. I'll PM my cell number. Bob

Partial water changes do not hurt, but they will not solve the problem or even put a noticeable dent in it and the reason is quite easy to understand--dilution. Let's assume, for simplicity, that there are no additional nutrients being added (not a valid assumption, but humor me on this one please) and you perform 10% daily water changes. The first water exchange removes 10% of the excess nutrients, leaving 90% of the nutrients behind. The next 10% water change only removes 9% of the original excess nutrients, leaving 81% behind...81-10%= 72.9...72.9-10%= 65.61. Because of dilution, each subsequent water change removes an even smaller percentage of the original nutrients. A 100% water change as Dave did will remove most, but not all excess nutrients since they are also bound in the sand and rocks and will be released into the new water. Personally, I would take a combined approach to many of the recommendations you've received so far. I'd target one two of the variables that allow HA to grow (phosphates, light/spectrum, nitrates), probably starting with phosphates. I might throw in one or more of the critters that love to eat HA (again, only masking the problem but making the tank look a little better). I would also recommend that you evaluate what you are feeding and how much since many commercial foods, especially frozen foods, contain high levels of phosphates and nitrates. I would continue with routine water changes, maybe doubling the volume for the next few weeks, and continue pulling excess HA by hand as often as possible (helping to export the excess nutrients in the process). Algae scrubbers are great, but add even more complexity to your tank maintenance and can produce some nasty smells if they are not properly maintained. Most important, be patient and methodical. You'll win the battle once you identify and correct the primary root cause(s).

Jan, There are many things you can do to make the HA go away, but all of them in isolation only mask the underlying problem. For HA to grow out of control, you need several things: - Light of the appropriate spectrum (and it is broad) and duration - Nitrates - Phosphates - Lack of herbivores that will eat HA Eliminate any of the first three and the problem is gone. Reduce any of the first three and the problem will become less severe. Add lots of the last item and the problem will either go away or you will have fat and happy herbivores. Although I did not have a major problem with it, my personal experience with HA was that I had elevated phosphates, accompanied with slight but almost unmeasurable NO3. I cut the lights for several days (coral actually liked this!), used some phosphate removers, and ordered a few extra snails for good measure. The problem went away. HTH

Assuming you remove the UV unit to place the end cap on, could you create a short section of PVC pipe with an end cap firmly glued on, then use one of the rubber sleeves with hose clamps to attach it to the existing pipes?

I'm all out of questions then, but I may have to come out of hibernation for the meeting!