Help me figure one thing out about OTS

[Leonard]

I've longed theorized Old Tank Syndrome may be an acculumation problem rather then a depletion problem (read my questions in this thread (http://archive.reefcentral.com/vbulletin/showthread.php?threadid=48316&perpage=40&pagenumber=1) ).

But the answer to one question eludes me:

If acculumation is the cause of OTS, wouldn't a large (80-100%)water change effectively remedy this problem?

A person may attribute OTS to the gradual buildup of toxins within an organism. And everyone agrees that chronic exposure to toxins and toxicants will inevitably lead to mortality. But the vexing problem with this theory is: corals introduced at different times (range of months and years) are reported to suffer the effects of OTS at the same time. This follows no logic, and instead points to acute exposure to acculumated trace elements in the water column. But if this is the case, shouldn't large water changes solve the problem?

Your article is sensible, except for the recommendation to reestablish tanks every 4-5 years (or any amount of time, for that matter). Shouldn't larger water changes suffice?

Thanks.

[rshimek]

See my article in the April [rk].

It discusses the effects of water changes. Basically as long as the water we are adding is contaminated, the best we can do is stay contaminated....

[Leonard]

That reminds me of a question I had concerning that article: Why do water changes not remove a proportional amount of major, minor, and trace elements? If you changed 100% of the water (or at least did successive 100% water changes), shouldn't the new values be theoritically returned to pre-OTS?

I understand the best we can do is maintain contaminated water. But if we can return the chemical values back to "new" saltwater (ie parameters when organisms are sustainable), doesn't that accomplish what most of us are trying to achieve?

[rshimek]

Originally posted by Leonard

Hi Leonard,

That reminds me of a question I had concerning that article: Why do water changes not remove a proportional amount of major, minor, and trace elements?

They do.

If you changed 100% of the water (or at least did successive 100% water changes), shouldn't the new values be theoritically returned to pre-OTS?

No, because there are other sources of nutrients and trace metals (= foods and additives). Some of these will remain in the tank with each change, and in fact they would accumulate.

But if we can return the chemical values back to "new" saltwater (ie parameters when organisms are sustainable), doesn't that accomplish what most of us are trying to achieve?

Maybe, except as this month's article shows, that newly mixed salt water has levels of heavy metals that are toxic to some animals. In effect, without a change in salt water type - to some new salt - or to natural salt water - the best you (or I :() can hope for is a polluted stressed system.

[Leonard]

I wholeheartedly agree better salt mixes should be expected/demanded. The reason I posted is I can't rationalize why one should have to reestablish their tanks every X amount of years. I'm still unclear why water changes can't be used to effectively dilute acculumated pollutants (via foods, additives, etc.) if they're large and/or done in multiple succession. At the very least, they should drive the chemical values back to pre-OTS levels - a point where most desirable decorative organisms are once again sustainable (even if the water is still a chemical cespool because of the nature of today's salt forumlas).

My apologies for the long, drivelling sentences :p

[rshimek]

Hi Leonard,

The problem is not driving things back to pre-OTS levels; it is that the tanks contain a toxic solution from the beginning, and really there is NO safe level with today's average salt mix.

The organisms in our tanks are pollution-tolerant organisms; nonetheless, they all are stressed by these high chemical levels. In a very real sense, OTS starts the day the tank is set up.

[pojohnny]

My understanding is that the 'chemical cesspool' part of freshly mixed saltwater is absorbed by the LR and LS.

Dr. Ron,
How long would you say that I should run my freshly mixed saltwater through GAC and floss before I do a water change?
Enough to turn the volume over a couple of times? or even longer?

Thanks in advance,
po

[rshimek]

Hi,

I really don't know. I will probably run my freshly made sea water through a canister with a polyfilter and GAC for about 24 hours before use. I still have to have some discussions with the polyfilter folks about this.

My guess is that longer times are better than shorter times.