Great to see so many people taking part in this discussion.
I don’t think OA or anything else is a good substitute for good fish husbandry, all fishkeepers need to learn about the environment they maintain their fish in, understand their fishes requirements and how to provide these, they need to understand the nitrogen cycle and how a biological filter works etc etc. I always work on the principal that I don’t keep fish I keep water, if you provide the right conditions the fish will look after themselves 99% of the time, the obvious exception being disease, but disease outbreaks are much reduced by maintaining fish in the right conditions to start with.
What OA does for new fishkeepers is allow people read, get involved in forums and learn while their fish do not suffer. How many new tanks are sold to inexperienced fish keepers and then stocked within a short period resulting in fish stress and death? Unfortunately even when a shop 100% accurately explains to a new customer how they need to go about cycling a tank or getting used filter media and starting with small numbers of fish that does not guarantee disasters will not happen either through the impatience of the new owner or the inability to spot early signs of stress, over feeding etc.
There are a few other things about OA that should be mentioned, some already covered above others I have not seen mentioned, it would be good to get some feedback from the distributor on these points.
OA clouds the water?
I have not found this to be a problem generally, although one tank did go cloudy for a few days after I started using OA, the fish showed no sign of stress and it cleared in a couple of days. I would be interested to know what causes the clouding, is it a bacterial bloom. Other tanks I started at the same time in the same way did not cloud at all.
OA tanks need to have their hood left open?
OA tanks need an airstone to assist the dissipation of nitrogen gas for the water, there needs to be room for the gas to escape and not sit on the surface blocking oxygen take up. How much does the lid need to be open by, for how long.
You can’t test OA tanks?
Traditional Nitrate, Nitrite and Ammonia tests will not give useable readings. The reason for this was explained before to me, but I would like to hear that again.
OA and pH?
You can test water for pH when using pH and the effectiveness of OA depends on the pH of the water, it is most effective at higher pH levels with an optimum at 8.0, ideal for African cichlids, below 6.5 it is not effective at all. Those figures need to be confirmed, it would be interesting to understand why too.
You can use OA in a power cut?
Someone asked me before if OA would keep their biological filters alive in a power cut, my understanding of how OA works work suggest this would be a bad idea. OA bacteria would compete with traditional bacteria in the filter. OA requires washing tradition filters in tap water to destroy the traditional bacteria. However in the event of a long power cut where the traditional bacteria filters have died OA could be used to get the tank going again, rather than recycling.
In a power cut what happens an OA tank?
With the airstone turned off, how long until the build up of nitrogen take before it starts to adversely affect the fish? What’s the best thing to do in this circumstance?
OA and plants?
As I don’t active grow plants I have no experience on the effects of OA on a planted tank. I understand there is a separate OA product for planted tanks. Why does the original not work with plants, if that is the case??
Breeding fish in OA?
My only personal experience of fish breeding in OA is Corydoras schultzei, they spawned unexpectedly and I raised some fry, there did not appear to be any difference from fry raised in a traditional environment, I would be interested to hear have other people bred fish in OA and did they find existing breeders more of less likely to do so.
Some people are giving out about the lack of information on how this product works. There are enough people on the forum here that have used it or are using it to build up quite a bit of information.
I am tempted to do another test of two side by side tanks with identical fish in each and run one traditionally for 6 months and use OA in the other and monitor the results, maybe I will put that on the short finger…
Daragh