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View Full Version : OT - Jacuzzi water treatment advice requested



DickDastardly40
07-10-2010, 06:03 AM
Guys,

The jacuzzi on the boat i work on has a persistant scum line and 'manky froth' despite having the water changed more times than I can count and a veritable witches brew of all the relevant chemicals added at each occasion.

We have just had a protracted yard period where the tub was empty. The tub does not regenerate the water from the overflow back into the pool but overboard. There is a circulation pump and heater with a suction strainer and sand filter and 2 separate massage jet pumps.

The only thing not cleaned or changed is the sand in the filter, which hasn't been done since the problem manifested as we are now on charter.

Do you think that the sand filter could be chock full of grease and sun oil despite being back washe and rinsed many times and the only solution is to change the sand?

Pretty much fresh out of any other ideas; 26 years engineering in the RN didn't prepare me for hot tub maintenance 101 :-)

Will take a pic the next time I go up to show what I mean.

TIA

Duffy
07-10-2010, 10:58 AM
Almost certainly it is the sand filter. It probably has developed the grease-equivalent of mud balls. The only cure is to empty the filter, WASH it thoroughly, and replace the media.
Since sunscreen and other oily stuff are known contaminants, it might be better to consider either a diatomaceous earth filter, (a royal pain to recoat,) or a high quality cartridge-type unit. The refills are expensive, but you change them out every charter and include it in the cost. I think that a spotless jaccuzzi is an essential requirement in the charter business. Also, you can carry spare cartridges and change them whenever necessary.

reggie_obe
07-10-2010, 11:34 AM
I fail to see how a D.E. filter would improve water quality, other than to capture an hold finer particulates. The filtration system, media and all are probably coated with biological contaminants that backwashing alone isn't ever going to remove. Are you using Chlorine or Bromine in the system? You might want to consider adding an ozone generator after cleaning the system out with a degreaser and replacing the sand media. If you can get a foam fractionator for the filter system, you can remove the organics before they buildup to problem levels.

Duffy
07-10-2010, 06:31 PM
DE wont improve water quality over a CLEAN sand filter. It is just that you throw the filter media away with the contaminants. This is, after all, only a fancy Jacuzzi, not a marine tropical aquarium. Oily bodies are going to play hell with the system, (unwashed, non-oily bodies are bad enough!) No matter what you use, you will have SOME difficulty. I was suggesting alternatives that would minimize the problems, not maximize the complexity. That is what prompted the cartridge filter suggestion.

reggie_obe
07-10-2010, 06:44 PM
I agree that having a cartridge would make cleaning of the filter easier, but you'd be tossing away, quite a few expensive reusable cartridges in a season along with the biological contaminants. Guess that's just one of the costs in the charter business.