Reverse osmosis ?

[LukeeVassallo]

Hi,

I have an angelfish pair currently in hard water ( pH varies from 8.1 - 8.4 ), and I am thinking that with an RO system I might solve this problem. Until now they bred 3 times ( once per 10-15 days ) but the eggs turn white everytime and they finally eat them all. Could this be due to hard water ? And what other advantages and disadvantages are when using an RO system.

Thanks a lot for you help,
Cheers
Luke

[Cliff]

I can't help you with your question about the eggs as I have never bred angel fish before

In most cases, RO water is pure, with 0 TDS (total dissolved solids). With all the minerals removed, your water has no pH buffering abilities and will most likely become highly unstable.

I would suggest that if you are going to use RO water, you could try mixing it with your tap water (60/40 or 50/50) or use a RO water additive that replaces all the minerals that are stripped out by the RO unit typically giving you a stable pH of 7.0 to 7.2. The use of RO water and the mineral additives/replacements is a some what common practice for discus owners if there tap water is not the best

[Honey Badger 1]

If your angels are tank bred they may just not have the hang of it yet and need more time to figure out what they need to do. You may even have two females. I've seen this happen on occasion. As Cliff says, use caution when trying RO water in a fresh water system, the bacteria needs the micro-nutrients the RO system removes so you will need to mix it with tap water or replenish them with additives.

[Sandz]

White means unfertile... RO isnt needed. Make sure #1 that the angels are indeed male/female when their breeding tubes drop. #2 make sure that the male is following up the female. It may just be they arent good at it yet and will take a while to get going.

What do you plan to do with the fry?

[FreakyFishie]

Most anglefish in the aquarium trade nowadays are able to accept and breed in a wide range of water values due to having been domesticated for so long, unless they are direct wildbred angels, then you shouldn't have a problem. RO water adjusts itself to the parameters of the water it is added to because of the fact it contains no minerals, therefore, just using RO water will not make your water softer or more acidic and it will kill your fish because fish require minerals in their water, the minerals are also what keep your pH stable. Hence why keeping a true soft water tank is difficult because there are less minerals in the water, making it susceptible to pH swings where as hard water tanks like for african cichlids don't tend to suffer from pH swings because of all the dissolved minerals in the water. If you truly want a soft water tank, since you already your tank set-up you will need VERY gently ease the fish into having soft water. Adding driftwood to the tank and peat moss to your filter will slowly soften your water from the moss decomposing and the tannic acids released from the driftwood. However, when doing water changes you will HAVE the pre-adjust the water going into the tank or it will ruin the soft water and stress your fish, potentially killing them. I personally use a mix of RO+tap+chemicals to alter the tap to keep my soft water tank.