[bongobrian]

I'm using a kent marine R/O unit, I believe it is the 35 gpd HI-S model, and my product water has 0.1 ppm of phosphate still in it. Has anyone had this problem? the unit is fairly new so I wouldn't think the membrane needs to be replaced yet. I've only used the unit about 10 times to make 5 gallons each time. My main water supply is well water, so I'm not sure if that is contributing to the problem. I tested my well water and it was around 0.5 ppm phosphate. Just wondering if the R/O unit is supposed to get rid of ALL phosphate in the water.

[Steve]

What brand of test kit are you using?

Do you have a RO or RO/DI unit? The RO filter is suppose to filter out 95%-99% of the impurities. You may need a DI canister to get the last of the phosphates.

[bongobrian]

Steve, thanks for your reply! I believe I am using an R/O unit. It is the Kent Hi-S model. It has one membrane and two canisters. One canister is the sediment filter, I'm not sure what the other is. My test kit is by Red Sea. The reason I'm posting this question is because my tank is having severe phosphate problems and I'm trying to identify the source of it. My tank usually has between 0.5ppm and 1.0ppm of phosphate. I know this is terrible but I don't know what to do about it. I've had a refugium up and running for almost 2 weeks now and that isn't helping. I've tried phosphate sponges, and I barely feed my fish, I feel like I'm starving them! and still my phosphates are out of control! after using the phosphate sponges, my level starts climbing again just days later. I can't figure out where this massive amount of phosphate is coming from. 0.1 is coming from my R/O water. I tested my salt and it doesn't contain any phosphate. I'm not adding anything organic to the tank other than food. Can anyone help me out? Thanks.

[bongobrian]

I also wanted to ask... how often does everyone clean their protein skimmers? I have a bakpak and the blue "bio-bale" is almost full of brown "gunk." I'm wondering if this gunk is contributing to the phosphate problem. I havn't cleaned the skimmer in about 4 months now. Is it important to keep the bio-bale clean? a guy at my LFS told me not to clean it very often, and if I did to just shake it off and only rinse it with tank water. Was this good advice?

[Steve]

I have found the Red Sea phosphate test very unreliable. Try to pick up a Salifert phosphate test kit if possible. Have you tried these at all: http://www.petwarehouse.com/webstore...f?OpenDocument
I bought some but didn't use them after switching from my Red Sea test kit to Salifert. I did give them to people who were having phosphate problems and it cleared them right up. I use a Kent Hi-S RO/DI. I have never tested the water coming out of the unit, but my aquarium water tests at 0.
How long has your tank been set up? What kind of food/s do you feed?

[Steve]

What do your nitrates test at? The bio-bale may be the source of your problems. You should try to keep it clean if possible. Yes, only rinse it with water from your aquarium or you will kill the bacterial colonies that have grown on them. A good time to do it is when you do a water change. If you are not having a problem with ammonia or nitrite and you have additional filtration for establish bacterial colonies, then you could rinse the bio-bale with other water.

[bongobrian]

My tank has been set up for about 4 months now. I havn't ever tried those pads but I'd be a little skeptical that something so small is going to remove the phosphate in my tank. I've tried large phosphate sponges which removed most of the phosphate, but like I said it came creaping back in a day or two.

Why is the Red Sea kit unreliable? just curious. Do you think it shows higher/lower levels than the actual correct level?

I was just curious last night and I tested some distilled water from the grocery store with the Red Sea kit and it measured out at 0.1ppm of phosphate! I thought that was interesting.

[bongobrian]

nitrates are at 20ppm and seem to be falling.

[bongobrian]

Steve, I just read your profile and just thought I'd mention that I have an EcoSystem filter set up with bioballs, miracle mud, and some flourishing caulerpa algea.

[Steve]

Sounds like our set-ups are pretty comparable. Whenever I tested with the Red Sea phosphate test, it would register .2 or .02? I can't remember. Whichever is the lowest on the scale. It would always measure the same no matter what. I lent the test kits to a friend for her to test her water, and it tested out the same as mine. Hers was a completley new setup where mine was established. She was having an algae bloom and I found it hard to believe that her phosphates were .2. Turns out she has a TDS problem and things are much better since getting her new RO unit. Perhaps the Red Sea tests are fine to measure higher levels of phosphates. The same water with my Salifert phosphate test kit registered 0. I don't know what else could be causing the high phospates. Do you feed any liquid foods?

[Steve]

By the way, are you using your protein skimmer on the same tank that has the Ecosystem? If you are there really isn't any need for it.

[bongobrian]

Yes, I am using both the ecosystem and the protein skimmer on the same tank. Reason being that I think my ecosystem is a bit small for my tank. It is the ecosystem40 which is rated up to 40 gallons, my tank is a 46 gallon. You bring up a good point though because since I started using the ecosystem, my protein skimmer hasn't been pulling out much dark skimmate.. mostly only clear foam. Do you think I should go skimmerless? It might be worth a try, my tank only has two fish in it, a medium sized yellow tang and a medium sized maroon clown, many corals and one bubble tip anemone.

I don't feed any liquid foods, only omega one flake food. Other additives include: reef builder, reef advantage calcium, lugol's iodine, and reef vital DNA. That's it for additives other than the occasional ph buffer.

[Steve]

Since you are running the Ecosystem, I would try to keep the bio-bale clean. It shouldn't matter if you kill the bacterial colonies on them since you have another source of filtration. Try to get the brown gunk out. That is a good place to start. You can use the skimmer, it just may not be necessary.

[AquaFx]

FYI

I am reading this post and I wanted to add some information.

There was a bad batch of Desal Membranes. I had the problem with the 50 and 100 GPD. I don't normally use 35 GPD membranes.

The tell tale signs are High TDS, lower (alot) then expected production and of course,contaminent break through.

The person who sold you this should be aware, if not tell them. They should replace it, if it is a Desal membrane. Due to the fact it is a new unit, it makes me think this could be your problem.

One other fact, there are TFC and CTA membranes. There is not a membrane manufactered that removes silicates differently. I heard that some RO's manufacturers check their rejection rates, but if this were true, it would have shown up that this was a defective membrane.

With all that said, it just might be your test kit.

Marianne