For the past 6 months I had been battling a low level but increasing algae concern. I made the assumption that it was due to leeching from some of my rock.
Was making my own water with an RODI unit. I used a standard setup which includes a carbon filter, micro membrane, and de-ionizing unit. The point of this is to remove all potential contaminants (total dissolved solids (TDS)) from the water.
Why? Any dissolved solid from municipal supply contains potentially harmful contaminants which may lead to growth of various algae or may potentially threaten your tank. Tap water may contain a screen reading of hundreds of TDS, whereas the RODI we want to put in our tanks should be at 0 (before adding salt).
So we use a RODI (Reverse Osmosis De-Ionizing) unit which removes all contaminants and drops the TDS to 0. These units often have an optional TDS meter which may be purchased to monitor the unit and ensure it it working properly.Or, you can order a unit to test the water manually.
I was making water without a TDS indicator built in.
I was using a hand held RODI tester to test water whenever I made it.
After a year of all being well I stopped using it, because I got lazy.
After this 6 month battle, a tank change, and continued algae growth, I investigated.
My RODI, even with new filters, was producing RODI water with 40-80 TDS.
I was using the same batch of DI resin throughout this time (which I got cheap).
I changed out the resin with brand new resin I ordered off the net.
My RODI dropped to 0-1 TDS.
Seems I had a bad batch of DI resin initially and I was using it for months, feeding the algae in my tanks.
So, I'd advise checking the TDS manually on a regular basis if you do not have an in-line indicator.
I'd also advise purchasing verified or positively reviewed DI resin - cheap does not mean effective.
I ran a batch of water tonight using the previously ordered 'cheaper' resin, and my TDS was at 72.
I refilled the resin with a new quality (and more expensive, by $3) resin and my TDS was at 0.
Take home message...
If you're running a RODI change all filters as required, and don't get lazy testing TDS.
If you're refilling de-ionizing cartridges manually, don't skimp on the resin, buy a decent product.
Was making my own water with an RODI unit. I used a standard setup which includes a carbon filter, micro membrane, and de-ionizing unit. The point of this is to remove all potential contaminants (total dissolved solids (TDS)) from the water.
Why? Any dissolved solid from municipal supply contains potentially harmful contaminants which may lead to growth of various algae or may potentially threaten your tank. Tap water may contain a screen reading of hundreds of TDS, whereas the RODI we want to put in our tanks should be at 0 (before adding salt).
So we use a RODI (Reverse Osmosis De-Ionizing) unit which removes all contaminants and drops the TDS to 0. These units often have an optional TDS meter which may be purchased to monitor the unit and ensure it it working properly.Or, you can order a unit to test the water manually.
I was making water without a TDS indicator built in.
I was using a hand held RODI tester to test water whenever I made it.
After a year of all being well I stopped using it, because I got lazy.
After this 6 month battle, a tank change, and continued algae growth, I investigated.
My RODI, even with new filters, was producing RODI water with 40-80 TDS.
I was using the same batch of DI resin throughout this time (which I got cheap).
I changed out the resin with brand new resin I ordered off the net.
My RODI dropped to 0-1 TDS.
Seems I had a bad batch of DI resin initially and I was using it for months, feeding the algae in my tanks.
So, I'd advise checking the TDS manually on a regular basis if you do not have an in-line indicator.
I'd also advise purchasing verified or positively reviewed DI resin - cheap does not mean effective.
I ran a batch of water tonight using the previously ordered 'cheaper' resin, and my TDS was at 72.
I refilled the resin with a new quality (and more expensive, by $3) resin and my TDS was at 0.
Take home message...
If you're running a RODI change all filters as required, and don't get lazy testing TDS.
If you're refilling de-ionizing cartridges manually, don't skimp on the resin, buy a decent product.
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