RO/DI not cleaning phosphate + a frozen food test

[firebirdude]

So I've been battling green cyano for nearly 2 years now. It will grow on anything in my tank. Sand. Rocks. Zoas. It knows no bounds. I've posted on here about it many times and have tried everything. Shortened lighting to 6 hours total, reduced feeding to semi-daily, dropped pellets in one at a time and made sure none went uneaten. Still cyano. Siphoned it out and kept up on water changes. Still cyano. Added cheato to the sump and it grew well. Still cyano. Bought a canister filter and use BRS GFO. Cheato slowly died off and still cyano.

Now then. I've tested my RO/DI output and posted results/pictures on here. They show phosphate in the DI output. Two different TDS meters read ~169 at the input and 0 at the output. People generally seem to not believe me. Tell me I must be measuring wrong, call me a liar about the TDS readings, tell me my test kits are faulty, etc etc etc. I've replaced the membrane, sediment filter, carbon block and DI resin several times and I've cleaned the RO/DI housings and replaced the tubing. I realize the API test kits do not give laboratory grade accuracy. But when I do side by side comparisons of tap water, DI output and tank water and you can see a clear difference between tap and DI from the tank water, THAT MEANS THERE IS SOME AMOUNT OF PHOSPHATE PRESENT. I don't care what the measurement is. It's not important. The tap and DI water easily show a more positive result for phosphate than the tank water (I understand the 0 for the tank water, let's not get into that).

I was curious how much phosphate was in a frozen food I occasionally (x1 a month maybe) feed mainly to the corals. I also took this opportunity to test all my waters again.
http://img6.imageshack.us/img6/8379/dsc01857kw.jpg
http://img850.imageshack.us/img850/6527/dsc01859w.jpg
http://img694.imageshack.us/img694/3296/dsc01860dy.jpg
Sorry for any poor lighting or shadows. But let me clearly state the DI output is plainly different than the tank water in person. It matches dead on to the tap water.

And yes the frozen food was packed with phosphate. I expected this, but hoped a few rinses would clear it out. It was a PITA and didn't seem to help but a tiny bit. I'll probably just stop feeding this. I do not feed phyto.

The real issue is why my DI water contains phosphate????!?!?

[jeff@zina.com]

First, phosphate can easily bypass RO/DI and not be measurable in any TDS. Second, food has phosphates. But the real issue is that there are ways to deal with this in the tank. Running macroalgae in a sump for example. A turf alga scrubber. Chemical products like ChemiPro Elite. I know you've used them already with little effect.

Technically, cyano is a bacteria and it really doesn't feed on phosphates as much as other forms of algae, so if you have cyano problems and no other algae issues I'm still not convinced it's a phosphate issue. But I do love the testing, now I don't have to try it. :)

Or actually, maybe I do...

Jeff

[Lynnmw1208]

wow! those results are really helpful! goes to show you how dirty frozen food really is!! glad I feed pellets 90% of the time! I agree with Jeff that you can always use other exports of phosphate. I use cheato in the sump and it grows like crazy! plus GFO. Thanks for showing us this! I hope you can solve your issue with the cyano!

[dzhuo]

First, phosphate can easily bypass RO/DI and not be measurable in any TDS.

Huh? How? A functioning RO/DI unit shouldn't let any phosphate pass through. A RO unit would not trap any phosphate but the DI resin should caught all of them since phosphate is negatively charged.

OP, have you checked tap water to see how high phosphate is? If you have recently replaced your DI resin, I would talk to whoever sell you the DI. It's either faulty or your membrane isn't working or filed up or your tap water is ridiously high with impurity which exhausted the membrane and DI resin quickly.

[firebirdude]

First, phosphate can easily bypass RO/DI and not be measurable in any TDS. Second, food has phosphates. But the real issue is that there are ways to deal with this in the tank. Running macroalgae in a sump for example. A turf alga scrubber. Chemical products like ChemiPro Elite. I know you've used them already with little effect.

Technically, cyano is a bacteria and it really doesn't feed on phosphates as much as other forms of algae, so if you have cyano problems and no other algae issues I'm still not convinced it's a phosphate issue. But I do love the testing, now I don't have to try it. :)
Thanks Jeff. I only have two small fish, use a skimmer, and keep up on the water changes. So I can't imagine my nitrate levels being an issue either.:( I used LEDs for the past year and a half, so no skewed bulbs or anything like that. I switched to a 250MH about two weeks ago. Corals look better, but cyano hasn't gotten better or worse. Don't know what's left. :uhoh2:


OP, have you checked tap water to see how high phosphate is? If you have recently replaced your DI resin, I would talk to whoever sell you the DI. It's either faulty or your membrane isn't working or filed up or your tap water is ridiously high with impurity which exhausted the membrane and DI resin quickly.
Please read the post and look at the pictures. The tap water is in the 2nd picture and I said I've tested it many times. My RO/DI has been suspect for over a year. As I've said, I've replaced everything in that system multiple times from multiple sources. I also said my TDS at the tap is ~169 which, from what I've seen around Ameirca, is pretty good.

[dzhuo]

Yes I read your entire post. But seems like you missed my point:

You are not suppose to have any phosphate from a working RO/DI with new resin and membrane. If you do, you need to talk to whoever sell you those and ask them why. You are spending money and getting faulty products. Or your water is high in impurity which exhausted the RO/DI quickly. Using GFO or any other phosphate binders to combat a known phosphate source seems counter productive to me. Every single drop of top off or water change, you are simply adding phosphate back so why running GFO and have them exhausted like that?

Have you talk to the vendor who sold you the membrane and resin?

[firebirdude]

I bought a new membrane, a sediment filter and two orders of DI resin from BRS. I haven't talked to them, but literally 1/2 of the users on Reef Central use BRS. I doubt the specific products they shipped me, on two separate occasions, were faulty. I've also bought a sediment filter, carbon filter and DI resin from a LFS. No change in results.

I would certainly agree that 0 TDS DI water should not contain phosphate. But I really don't know enough about the science of it for my opinion to really count. lol

You know.... something I haven't done.... I haven't just used DI water from the grocery store. Maybe I'll try that for a few water changes/ ATO water for a month or so. See if that makes any difference.

[jimrawr]

Are you testing the water directly as it comes out of the RODI or are you keeping it in a holding tank and then testing? Its possible if you are using a holding tank that it could be leaching po4 from the plastic I would imagine

[dzhuo]

I would still suggest that you talk to BRS about this issue. It's highly unlikely it's a faulty product (if it's from BRS) but they might be able to help you figure out why. Other than a fault membrane or resin, about the only other reason why you would see such a high phosphate from a working RO/DI unit is either the membrane or resin has been exhausted. But since they are new, it can't really be. Most resin is color coded (using pH as indication) and should be black (high pH). When the resin is exhausted, it turns into brown (low pH). Have you notice a color shift?

The reason why clean RO/DI should not contains phosphate is because phosphate is negatively charged and a resin is designed to trap any charged molecules. When the resin is working properly, phosphate would not have escaped. If your resin is not working, it's much worse than not using one. One would expect using a depleted resin is like not using one but that's not the case. A fully depleted resin could potentially release a lot of ions or any trapped molecules back and cause all sort of problems.

I think it's worth talking to BRS to see what they have to say.

[firebirdude]

***!

So I had nothing better to do and went to Walmart to stock up on DI water to see if it helps. I throw away all my DI topoff water and refill it with fresh out of the bottle DI water from Walmart. About 1/8 gallon wouldn't fit, so I figured what the heck... let's test it for phosphate.
http://img846.imageshack.us/img846/1440/dsc01862q.jpg
http://img200.imageshack.us/img200/9895/dsc01863d.jpg

***! It has the same amount of phosphates in it that my DI system and tap put out!

Again. I realize these test kits aren't lab grade or anything. But the fact you can see a noticeable difference is really all that matters.

:furious::furious:

[jeff@zina.com]

I only have two small fish, use a skimmer, and keep up on the water changes.
Cyano really only feeds on light and oxygen, not much else, so I still don't think it's a nutrient issue. Have you done the three days dark routine? (Can't remember your other thread...). Other algae, like hair algae, would grow faster and better than cyano if you had a nutrient overload.

Jeff

[hollister]

Phosphate, like nitrate, accumulates in aquarium water over time. Phosphates can become a problem if allowed to exceed allowable concentrations. Excessive phosphate concentrations can affect the health of invertebrates as well as contribute to the undesirable growth of algae. The excessive algae growth on rock in reef aquariums will prevent the desirable coralline algae from developing the concentration of phosphate should be monitored in aquariums. The testing of phosphate in reef aquariums is essential as part of the routine water quality monitoring.
It is important to note that phosphate occurs in both inorganic and organic forms. Many test kits only measure the inorganic form, also known as orthophosphate. Therefore, you can make an erroneous assumption that no phosphate is present if you are using a test kit that measures only orthophosphate. You should check with your pet store concerning the correct type of phosphate kit to purchase.
The source of phosphate originates from three primary sources: utilisation of food by the aquarium animals, decay of excessive food, and activated carbon and municipal water. You must be careful about not overfeeding, as this contributes to the build-up of phosphate. Make sure that whenever you purchase carbons they are phosphate-free. Most premium brands on the market will note on the label that the product does not contain phosphate. Tap water should also be tested to ascertain if phosphate is present. If your tap water always contains phosphate, you should consider using deionized water for your aquarium.
Phosphate levels should generally not exceed 0.2 mg/L for aquariums containing fish.

[firebirdude]

Cyano really only feeds on light and oxygen, not much else, so I still don't think it's a nutrient issue. Have you done the three days dark routine? (Can't remember your other thread...). Other algae, like hair algae, would grow faster and better than cyano if you had a nutrient overload.

Jeff

I haven't done the three days lights out routine. I agree that is sure to have a positive impact on it... but it seems that if the source of the cyano isn't cured, the cyano will just come right back. So what's the point? And I don't have any GHA, so that IS an interesting point.

Phosphate, like nitrate, accumulates in aquarium water over time. Phosphates can become a problem if allowed to exceed allowable concentrations. Excessive phosphate concentrations can affect the health of invertebrates as well as contribute to the undesirable growth of algae. The excessive algae growth on rock in reef aquariums will prevent the desirable coralline algae from developing the concentration of phosphate should be monitored in aquariums. The testing of phosphate in reef aquariums is essential as part of the routine water quality monitoring.
It is important to note that phosphate occurs in both inorganic and organic forms. Many test kits only measure the inorganic form, also known as orthophosphate. Therefore, you can make an erroneous assumption that no phosphate is present if you are using a test kit that measures only orthophosphate. You should check with your pet store concerning the correct type of phosphate kit to purchase.
The source of phosphate originates from three primary sources: utilisation of food by the aquarium animals, decay of excessive food, and activated carbon and municipal water. You must be careful about not overfeeding, as this contributes to the build-up of phosphate. Make sure that whenever you purchase carbons they are phosphate-free. Most premium brands on the market will note on the label that the product does not contain phosphate. Tap water should also be tested to ascertain if phosphate is present. If your tap water always contains phosphate, you should consider using deionized water for your aquarium.
Phosphate levels should generally not exceed 0.2 mg/L for aquariums containing fish.Nice copy and paste. LOL But helpful none the less.

I certainly can't imagine our test kits only measuring inorganic phosphate. That seems ludicrous for marine enthusiasts. And I'm using BRS ROX carbon. Supposedly the best stuff on the market.

[jimrawr]

have you tried red slime remover? Worked for me when dosed correctly and didnt return after that.

[thefishguy86]

when you used the red slime remover did you do any water changes or cleaning of the sand bed?

[disc1]

I'll help you with the 0 TDS water and phosphate problem. It's simple mathematics. You have 0ppm TDS, not 0 TDS. 0ppm means not enough to read 1ppm. When you measure it with your kit, you measure 0.25 or 0.5ppm. If the meter read 1ppm for 0.25ppm, then it would read 4 for 1ppm TDS.

Get what I'm saying? The zero just means less than 1. Just like 2 might be 2.3 or 2.4. It's like this with any measurement device. It's called precision. You can get a TDS meter that reads in ppb and it will probably read somewhere between 250 and 500 on your RODI water.

[funkejj]

Cyano will be cured with a 3 day light period. Man I have had high nitrates and phosphates did the lights off one time and it was gone. Never came back. Try it.

[papagimp]

It's called precision....

excellent response and so right on the money. The test kits i'm seeing his the OP's pictures are definatly known for their inaccuracy, but unfortunatly seem to be one of the more readily available tests and everyone seems to care them exclusivly (speaking locally, online is a whole nother ball of wax)
I'd also add that I've purchased one of those kits, used it for while, and when I purchased new ones to replaced my depleted test, the color charts would often be a different shade of the colors, enough that it would effect the overall reading. For the nitrates, nitrites, ammonia, no so much a big deal with em but for phosphates, everything i remember bout em is telling me they suck.

[Fish Biscuit]

I would try the lights out before adding chemicals to the tank.