Are whole house water filters a substitute for RO/DI??

[bimmer88]

A friend of mine just started his reef tank. Was having bad algae problems and asked me to take a look at it for him. Said he was doing his water changes with water from his whole house water filter system. At first I was thinking he just had a water softener but then when I looked at it, it looks like it's more than just a simple water softener. Attached is a pic. Anyone know if this does the same type of filtration as an RO/DI system?

[heathlindner25]

Pre filter and carbon only .

[nereefpat]

Not a softener for sure.

It's hard to tell exactly, but I agree it looks like some kind of mechanical filtration and maybe carbon.

[billdogg]

^^^this^^^

He could probably get away with just ro and di cartridges, but I would use a complete system with it's own prefilters just in case to protect the ro membrane and the di resin. If the whole-house prefilters are doing their job, then the prefilters on the ro/di should last a very long time.

[mcgyvr]

It is not the same as its lacking an RO membrane and a DI filter but both can be added to the output of that very easily.
Parts available at bulkreefsupply as well as many others..
You just need a RO membrane/canister and a DI filter/canister and some tubing/adapter fittings..


Now.. having said that.. There is absolutely no guarantee that their algae problems are due to that..
Algae problems are typically related to excessive nitrate/phosphate as well as being fueled by light..

What are the nitrate/phosphate readings of the tank?
Do the same tests on a batch of freshly mixed saltwater..
Post results for further instructions..

[d2mini]

As stated above, no DI on house systems.
What's the TDS of the output water?

[Dmorty217]

I have a whole house filter and still use a RO/DI

[CRJ]

Looks like sediment filters at most and some carbon. Great to hook a RODI unit to, bad to run a tank with.

[HBtank]

His filter is only designed to make water smell, taste, and look better than tap water. Basically just makes it better to drink and wash with.

It essentially does nothing in respect to reef tanks other than deal with chlorination (all tanks need that!) and some immediate hazards, and when used with a typical system most reefers have, they also reduce wear/tear on RO/DI filters (the "pre-filters"). Hard to know how bad his water is, but his city should have a report, if municipal water to give an idea of if it is the algae problem. I would go RO/DI regardless though...

[Kevin Guthrie]

They do make whole house RO systems. They don't look like the posted pic, more like huge DI canisters.

[avery155]

Definitely get a rodi system, it'll make sure your getting the purest water you can. What you drink will still have some tds. Rodi will read 0. You want to start with a blank slate when mixing your salt in.