difference between RO and HMA

[Zebra Pleco]

Hi all, I bought a RO Unit about a year ago, a 50 gallon a day thing, huge beast of an equipment, with storage drum, 3 cartridges and pipework everywhere.

I have never got round to installing it, as I know nothing about them, just bought it from a local neighbour in ebay.

I am now looking for triggers for my fish and thought about using this contraption, but have read an HMA unit is better.

Can I use a RO unit as an HMA filter or are these completely different. Will my RO unit still work after sitting around for a year, or will I need new cartridges.

And lastly, I am going to google how I connect this thing up, as I have never used one before. How will I know its working ok and do I need to do anything to the water afterwards, I read somehwere I need to add some stuff called RO Right.

Hopefully someone out there can help, if not its up for sale lol.

Will post pictures of the monster.

 

[macvsog23]

Hi

Finally got a RO unit?

Right RO is water that is stripped of most of the solid and suspended matter.
HMA is water that is stripped of the metals and a few heavy items.

RO water will kill fish if used neat and just dumped in to a tank.
My advice is get a HMA unit plumb it in along with the RO unit blend the water by adding the HMA to the RO get a TDS of around 200 and use the water to do 10% water changes.

Now to explain the bits on an RO unit.
Yours sound like a 5 stage unit I would think it has a membrane, 3 pods and a resin section.
First the membrane would by now be useless or at best so dry it will not work, any membrane left out of water for a few days will become damaged and if left in water for longer will have a build up of bacteria in it.
Try to think of your membrane as a piece of very fine cloth so fine it would trap any thing apart from water.
This membrane is the main key to your RO unit
Quality is varied you can spend over a £100 on a 24 GPD membrane and you can buy a whole unit that will produce 100GPD for the same money. Basically you pays your money you takes your choice. Cheap as always = crap
Membranes are rated in UG Gallons and calibrated at 70 degrees f.
In winter the water will be around 1 or 2 degrees c so your get nowhere near the rate on the membrane, do not use hot water to try to get around this problem, your damage the membrane beyond reclaim.
The 3 pods will contain a pre filter usually a 25 micron filter the next one will contain a carbon filter the final one may contain a resin for “Polishing your water”
Use good quality filters as they are not a lot dearer than the crap ones.

The resin will usually change colour when it is not working.

I would strip the unit and get some one who has used one to rebuild it for you, cleaning every part is vital as any crap will affect your water and cause you to get readings that are unstable.

If you wish I can strip and rebuild it for you.

A common misconception is that a RO unit will produce clean water and waste water that is total ******** it will produce rejected water and product water that you can use.
The rejected water will be as pure as what went in it just could not pass thought the membrane thus it is rejected. RO units produce around 3 times the amount of rejected water to product water.
The rejected water is of the same quality as the water that was used to produce the RO so it can be used; some people use it to add to the RO as a % of the total water.

 

[Zebra Pleco]

Ouch thank you for a very good reply, I will take photo's of it tonight and post it up here for you too look at. I only paid £50 for it a year ago on ebay, but unsure of the state of it. At work at moment, but get online tonioght and post some piccies.