Is my RO unit functioning correctly?

Question:

Hello,

I hope you can help me. I'm an active member of a marine fish keeping forum, and the members suggested I contact you.

I'm relatively new to marine fish keeping, but not to the fishkeeping hobby. I purchased a DD Solution RO Unit in March from my local retailer (Maidenhead Aquactics) and last weekend purchased an Add On (Di Resin). I have noted that the pure RO water is not dealing with the Phosphate levels, (I use the DD Phosphate test kit) hence why I was previously advised to buy the Di Resin, I still have seen very little differencein doing this. It seems that the membrane itself is non-functional. I'm a little disappointed, as I don't hear other people having this problem with RO-Man. I do hope that you can bring me some confidence back in the DD brand by replacing the RO membrane.

I look forward to hearing from you or your suggested advice shortly.

Kind Regards

Hemel

Answer:

Hemel

This is very strange as we sell many units every week and do not get this type of problem.

There is always the chance that you have a faulty membrane but these are very uncommon - if you think this is the case then go back to Maidenhead aquatics and we will look further into changing the membrane over.

The other issue is that the unit may not be connected properly which can happen.

Please check by going through the following.

1 - mains water into side of clear pod - fairly straight forward.
2 - with unit outside or over sink take off the flow restrictor from the orange pipe and switch on the mains water. You should get lots of water from the orange pipe and very little from the blue. If this is the case then the pipes are the right way round. If it is not the case then swap them over as you have been collecting the waste water.

3 - fit the flow restrictor back onto the orange pipe paying attention to the direction of flow and ensure that the black tap is at 90 degrees to the restrictor - ie not inline as this is in flushing position.

Allow to run for 20 minutes and check the water again

If this still does not result in pure water then it suggests a problem with the membrane.

Hope this helps

Stuart